TBR: hpayer@chromium.org
Bug: v8:6443
Change-Id: I1750475084cbcd783551d9b7c65c8ccca9b63ea3
Reviewed-on: https://chromium-review.googlesource.com/1045615
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53010}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/0a40aa9..506800f

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/39e3bc6..3059fd7

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: I3cc068e21babbe30dd36eb715209a1b6c3214441
Reviewed-on: https://chromium-review.googlesource.com/1046127
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53009}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/55b398a..0a40aa9

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/153134e..39e3bc6

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: Ibba9fa7e267b5b8b92cdb3d43776e62ae32abb30
Reviewed-on: https://chromium-review.googlesource.com/1045792
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53008}

Change-Id: I19106adfd5407cbef05142fde3b7eb00ecd8ff52
Reviewed-on: https://chromium-review.googlesource.com/1043256Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Eric Holk <eholk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53007}

In preparing for adding trap-based bounds checking to Windows, this
change refactors the code to separate the platform-specific portions
from that which can be shared between platforms.

Internally, we've renamed `RegisterDefaultSignalHandler` to
`RegisterDefaultTrapHandler` to more accurately represent the
difference in terminology between Linux (signals) and Windows
(exceptions). The external API is left the same so as not to break
downstream clients.

This CL is primarily to make room for Windows support. Future CLs
will begin adding support for Windows.

This is a reincarnation of https://crrev.com/c/626558.

Bug: v8:6743
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: Iaa8bfd68c14cd1d17933b12c24cb8dd5ee8a21d6
Reviewed-on: https://chromium-review.googlesource.com/998829
Commit-Queue: Eric Holk <eholk@chromium.org>
Reviewed-by: Brad Nelson <bradnelson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53006}

Change-Id: I450efa4916bd774265991f987f4be618ba2eb1d2
Reviewed-on: https://chromium-review.googlesource.com/1045168
Commit-Queue: Alexei Filippov <alph@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53005}

ProfilerListener which holds CodeEntries has been moved from Logger to
CpuProfiler. This way we can clear entries when all the profiles
produced by a particular CpuProfiler are deleted.

BUG=v8:7719

Change-Id: I31d47dc7da44648c8fb8e87b47e2e6260d3dc5c3
Reviewed-on: https://chromium-review.googlesource.com/1043050Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53004}

Creating a new instance from a v8::Function will invoke its
constructor. If it is an API callback that has not been marked as
kHasNoSideEffect, this CL introduces a way to invoke it without
throwing.

Calls within the constructor are still checked for side effects.

Bug: chromium:829571
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: Ia4e410d487e2847bc511cb96f0be30a3563991f6
Reviewed-on: https://chromium-review.googlesource.com/1034116
Commit-Queue: Erik Luo <luoe@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53003}

This makes {Script} objects created for WebAssembly no longer reference
a concrete instance object, but a module object instead. All uses of the
field in question only require module-wide information and the script is
meant to represent the set of all instances, not just one concrete
instance.

R=clemensh@chromium.org

Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: I751d4b75c8a970cffcb1a37b6c22ff69e9ee5489
Reviewed-on: https://chromium-review.googlesource.com/1043871Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53002}

Torque expressions of type constexpr are evaluated at compile-time
rather than runtime. They are backed by C++ types rather than
TNode<X> types, so the macro functions that are called by generated
C++ code expect values to be computed when the snapshot is generated
rather than by TurboFan-generated code.

Specifically, "if" statements can have a constexpr modifier. With this
modifier, a type of "constexpr bool" is expected rather than "bool",
and in that case instead of generating a CSA BranchIf, it generates
a C++ "if (<bool expression>)" that generates code for only the true or
false path based on the bool value at torque-execution (compile time)
rather than generating both paths (including inserting phi nodes
for variables modified on either branch at the re-merge at the end
of the if) and dynamically dispatching to the true or false path
during d8/Chrome/node.js execution (runtime) using a CSA BranchIf.

Change-Id: I8238e25aaadbfc618847e04556e96a3949ea5a8d
Reviewed-on: https://chromium-review.googlesource.com/1042085
Commit-Queue: Daniel Clifford <danno@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53001}

First untrusted code mitigation in Liftoff: Mask memory accesses (loads
and stores) by the mask stored in the WasmInstanceObject.

R=titzer@chromium.org

Bug: v8:6600, chromium:798964
Change-Id: Iddf577977451444b51c42fbc2ad34430832a9e71
Reviewed-on: https://chromium-review.googlesource.com/1044215Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53000}

Bug: v8:6600
Change-Id: I1bd2db402d6e97ab468dc24cd4d12bef6523d784
Reviewed-on: https://chromium-review.googlesource.com/1043091
Commit-Queue: Vincent Belliard <vincent.belliard@arm.com>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52999}

This method is intended for use by code caching as follows:

1. The module is compiled (and perhaps instantiated).
2. The embedder fetches and stores the module's unbound script (i.e.
   the shared function info).
3. Module evaluation, maybe triggering lazy compilation.
4. Generated code for the module (which hangs off the shared function
   info) is inserted into the code cache.

Subsequent module loads can load from the code cache prior to
evaluation.

Bug: v8:7685
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: I80018cd921ab1a18323906a548b249e19d9f9509
Reviewed-on: https://chromium-review.googlesource.com/1041745
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52998}

* Empty string literals (e.g. "" and '') were not recognized a strings. This is
  now fixed.
* return statements without expressions (e.g. for functions with void return
  types) caused crashes.

Change-Id: Ied60f9abffca457a0d85c9e01e3795839fe777c9
Reviewed-on: https://chromium-review.googlesource.com/1042310
Commit-Queue: Daniel Clifford <danno@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52997}

Bug: chromium:800348, chromium:827627, chromium:839750
Change-Id: I112e20b83eb1937476ebb4f30cf5679113759c0c
Reviewed-on: https://chromium-review.googlesource.com/1044195Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Hannes Payer <hpayer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52996}

On div and rem on ia32 and x64, we sometimes need to spill. If this
spilling code happens inside of a branch, the cache state will reflect
that the value was spilled, even though the actual spilling code might
not have executed.

R=titzer@chromium.org

Bug: v8:6600, chromium:839800
Change-Id: I93b681a23119f903feb54235d6d44a7cbd5815fe
Reviewed-on: https://chromium-review.googlesource.com/1044185Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52995}

The {baseline_compilation_units_} and {tiering_compilation_units_}
fields should only be accessed if the {mutex_} is held.
Also, the number of compilation units is already taken care of inside
of {RestartBackgroundTasks}, so no need to explicitly pass it.

R=ahaas@chromium.org

Change-Id: I8f36ed141b587ee1bea41291545f39546d8cf24e
Reviewed-on: https://chromium-review.googlesource.com/1044213Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52994}

Since address is a uintptr_t, there is no need to implement a specific
hasher.

R=mstarzinger@chromium.org

Bug: v8:7570
Change-Id: I47e652929ef201e742224541d9df4360444e3ba8
Reviewed-on: https://chromium-review.googlesource.com/1044209Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52993}

ExternalString::kShortSize is not the same as i::kShortSize, caused
incorrect reporting for code stats for two byte strings.

Bug: chromium:837659
Change-Id: Icbb39f2103aa4fa72bd5b1258cb8e1d4aee10441
Reviewed-on: https://chromium-review.googlesource.com/1044212Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Benoit L <lizeb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52992}

macros.h already not only defines macros, but also templatized helpers
like {bit_cast} and {arraysize}. Thus {implicit_cast} also belongs
there.

R=tebbi@chromium.org

Bug: v8:7570
Change-Id: Iaea6075dad359d62498453575f22d73ca84e2323
Reviewed-on: https://chromium-review.googlesource.com/1042401
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52991}

This CL factors the parts of the JSGraph that only depend on the
machine part of JSGraph into a separate base class, MachineGraph.
This helps separate the two layers and also allows the MachineGraph
to be constructed without an Isolate, which is needed for fully
asynchronous compilation, a goal for WASM.

R=mstarzinger@chromium.org
CC=jarin@chromium.org, mvstanton@chromium.org

BUG=v8:7721

Change-Id: Ie8bc3de40159332645dcb3cadcee581e1bf9830a
Reviewed-on: https://chromium-review.googlesource.com/1043746Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52990}

Add binop tests for div and rem of i32 and i64. The test is extended to
handle traps, and to check that the value of local variables is not
affected by the operation.

R=titzer@chromium.org

Bug: v8:6600, chromium:839800
Change-Id: I1a4cbc40bd399666d9831d021afb96e0c53a9f64
Reviewed-on: https://chromium-review.googlesource.com/1044166Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52989}

Bug: chromium:830557
Change-Id: I99bfa92f46a03782232e6949dd437afb5a3f6c26
Reviewed-on: https://chromium-review.googlesource.com/1043866Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52988}

In order to get more test coverage (also on ClusterFuzz), stage Liftoff
and tier up behind --future.

R=hablich@chromium.org
CC=​​titzer@chromium.org

Bug: v8:6600
Change-Id: I718e17957b26f60aa4c002333035f693344806e0
Reviewed-on: https://chromium-review.googlesource.com/1042385Reviewed-by: Ben Titzer <titzer@chromium.org>
Reviewed-by: Michael Hablich <hablich@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52987}

The Promoted* prefix was used to refer both to the total number of old
generation objects, and to the delta of objects moved from the new to
old generations.

PromotedTotalSize() is also renamed, to reflect the actual calculation
it performs

Bug: chromium:837583
Change-Id: Id27a0661618257ef64eb469a83bb49c0e8ce6923
Reviewed-on: https://chromium-review.googlesource.com/1042314
Commit-Queue: Wez <wez@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52986}

This is a reland of a0c57368

Original change's description:
> [wasm] Maintain link from Instance to Module.
> 
> This moves the link from a {WasmInstanceObject} to its corresponding
> {WasmModuleObject} into the right place and also makes it strong. This
> ensures that an instance always keeps the underlying module alive and
> hence removes the situation of an "orphaned instance".
> 
> R=clemensh@chromium.org
> 
> Change-Id: Id59f6a49740af8ef0248679c3d2c696bb9776944
> Reviewed-on: https://chromium-review.googlesource.com/1041691
> Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
> Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#52942}

Change-Id: I9854400bfc1d22bd258f17118fcb7460cdc3acd5
Reviewed-on: https://chromium-review.googlesource.com/1043786Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52985}

- In debug builds, 'assert(<expr>)' evaluates and aborts execution
  if the provided Torque expression is false at runtime.
  assert(<expr>) supports the same set of expressions protocols
  as Toruqe's if statement, i.e. both bool values and BranchIf-
  style tests. Upon failure, the assertion prints the Torque
  source code of the failed expression, not the generated CSA
  code.
- 'unreachable' calls CSA's Unreachable() and signals to Torque
  that code execution cannot continue (i.e. its statement
  returns the 'never' type). In debug builds, the line number
  and position of the statement are printed before breaking.
- 'debug' calls CSA's DebugBreak(). In debug builds, the line
  number and position of the 'debug' are printed before breaking.

Change-Id: I4efd052536bb402c097a0d5f7be56e154b5b3676
Reviewed-on: https://chromium-review.googlesource.com/1042570
Commit-Queue: Daniel Clifford <danno@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52984}

Instead rely on the scope info containing the name as well.

Change-Id: Ie1f96ea023a793b11209510566f6831b1dfd40ab
Reviewed-on: https://chromium-review.googlesource.com/1042567
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52983}

The CL fixes the mips port in the CL [debug] introduced runtime side
effect check (7a2c3713), that caused
several test failures.

BUG=

Change-Id: Ia1b45fd57d7b77c912562c97f7fc6bf2aa378fe2
Reviewed-on: https://chromium-review.googlesource.com/1030193Reviewed-by: Ivica Bogosavljevic <ivica.bogosavljevic@mips.com>
Commit-Queue: Miran Karić <miran.karic@mips.com>
Cr-Commit-Position: refs/heads/master@{#52982}

Bug: v8:7066
Change-Id: Icfcb40b2048997c158fba5f3e250145bed4ca1e3
Reviewed-on: https://chromium-review.googlesource.com/1042386
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52981}

Change-Id: I58f3eb9259822650a3b31010213e3df030821be2
Reviewed-on: https://chromium-review.googlesource.com/1042187Reviewed-by: Hannes Payer <hpayer@chromium.org>
Commit-Queue: Wez <wez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52980}

This makes sure that allocations of {HeapNumber} objects happening in
the JS-to-Wasm and Wasm-to-JS wrappers are ordered with respect to
changes of the {trap_handler::IsThreadInWasm} predicate. Otherwise the
compiler can (and will) move the allocations across changes of this
predicate and cause safety checks to fire.

R=clemensh@chromium.org

Change-Id: I5366ec0c184929fbd5b60c827d9908fb6ca1d91a
Reviewed-on: https://chromium-review.googlesource.com/1042399
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52979}

The grow_memory opcode basically just executes a runtime call, but
needs to check a condition first, and convert to and from Smi.

R=titzer@chromium.org

Bug: v8:6600
Change-Id: If7d62a8bb0ca6d02bd47ef6048cc65da502b002b
Reviewed-on: https://chromium-review.googlesource.com/1042185
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52978}

On arm64, we had {RegisterBase::bit} (defined in assembler.h) and
{CPURegister::bit} (defined in assembler-arm.h). {CPURegister} inherits
from {RegisterBase}. The two methods methods have different
behaviour on the special {no_reg}, which is only relied on in very few
places.
This CL fixes these places to avoid the use of {no_reg}, and removes
the overwritten method.

R=mstarzinger@chromium.org
CC=​rodolph.perfetta@arm.com

Change-Id: I859cc0d4ffc48fae018ee262f3e5403774db87a8
Reviewed-on: https://chromium-review.googlesource.com/1042188Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Rodolph Perfetta <rodolph.perfetta%arm.com@gtempaccount.com>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52977}

Side effect free whitelist now
- supports 'typeof' when it performs Load operations
- runtime checks for Array.p.splice

Bug: v8:7588
Change-Id: I45bcd705f8d3f2d2ee61f018566439bf56d1bcbc
Reviewed-on: https://chromium-review.googlesource.com/1037926Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Erik Luo <luoe@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52976}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/34746fc..55b398a

Rolling v8/third_party/android_ndk: https://chromium.googlesource.com/android_ndk/+log/635bc38..5cd8631

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/978be74..153134e

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: Id123826d5fd7df1c53f2e2bb36591c9e29e20833
Reviewed-on: https://chromium-review.googlesource.com/1043431Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52975}

Since 94ce16b7, when loading an iterator from null or undefined, we
generate the error message "x is not iterable" instead of the unwieldy
"Cannot read property 'Symbol(Symbol.iterator)' of undefined". However
Runtime::GetObjectProperty, which is used as slow path by LoadICs, did
not check for this case, leading to different messages being generated
depending on IC state.

Bug: chromium:823130
Change-Id: Ie98500b97efef401aac9880b9af47d58c3c2825d
Reviewed-on: https://chromium-review.googlesource.com/1042951Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52974}

Port 519bd47f

Original Commit Message:

    With the exception of the InterpreterEntryTrampoline, all builtins are
    now isolate-independent and can be embedded into the binary.

    This CL updates the corresponding list and also contains a few smallish
    tweaks to support having these builtins off the heap:

    * wasm: copy the off-heap builtin, not its trampoline.
    * Code::contains: support off-heap builtins.
    * JSFunction::is_compiled: compare builtin index instead of identity
      (this is relevant during mksnapshot when we transition from the
      on-heap builtin to its off-heap representation + the trampoline).
    * Remove old DCHECKs.
    * A few tweaks in macro-assembler ports that have snuck in recently.

R=jgruber@chromium.org, joransiu@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: Ib16ce35f5ebdade42720f536ac521c79e7c46778
Reviewed-on: https://chromium-review.googlesource.com/1042927Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#52973}

This is a reland of dfdc3135

Original change's description:
> PPC/s390: [interpreter] correctly advance over debug scaling prefixes.
> 
> Port 7a07d74b
> 
> R=yangguo@chromium.org, joransiu@ca.ibm.com, michael_dawson@ca.ibm.com
> BUG=
> LOG=N
> 
> Change-Id: I99553fde819cbdc8a12df5b82d9d7230ba4ef8b3
> Reviewed-on: https://chromium-review.googlesource.com/1042355
> Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
> Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
> Cr-Commit-Position: refs/heads/master@{#52970}

Change-Id: I012e79ef5fbff37a8ded8c8cf5d4aaf324cd6ccb
Reviewed-on: https://chromium-review.googlesource.com/1043026Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#52972}

This reverts commit dfdc3135.

Reason for revert: <INSERT REASONING HERE>

Original change's description:
> PPC/s390: [interpreter] correctly advance over debug scaling prefixes.
> 
> Port 7a07d74b
> 
> R=​yangguo@chromium.org, joransiu@ca.ibm.com, michael_dawson@ca.ibm.com
> BUG=
> LOG=N
> 
> Change-Id: I99553fde819cbdc8a12df5b82d9d7230ba4ef8b3
> Reviewed-on: https://chromium-review.googlesource.com/1042355
> Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
> Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
> Cr-Commit-Position: refs/heads/master@{#52970}

TBR=yangguo@chromium.org,michael_dawson@ca.ibm.com,jyan@ca.ibm.com,joransiu@ca.ibm.com

Change-Id: I04fadaa81a6dd124811c002ab4ffa61e3785b717
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/1043025Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#52971}