This is done now while embedders have yet to adapt to the new API before
it becomes hard to migrate.

Also renamed variable/methods to use "worker threads" rather than
"background" nomenclature.

Extracted from https://chromium-review.googlesource.com/c/v8/v8/+/978443/7
while resolving the more contentious bits around using task runners.

TBR=rmcilroy@chromium.org

Bug: chromium:817421
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: Ie3ddf15a708e829c0f718d89bebf3e96d1990c16
Reviewed-on: https://chromium-review.googlesource.com/980953
Commit-Queue: Gabriel Charette <gab@chromium.org>
Reviewed-by: Gabriel Charette <gab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52231}

With a temporary intermediate step to allow adapting embedders before
getting rid of the ExpectedRuntime method altogether.

The method is being renamed to CallOnWorkerThread() as an effort to
go away from "background" nomenclature for worker threads ("background"
usually refers to a priority but worker threads are commonly used for
high priority tasks in v8).
Other CLs will follow to rename other "background" APIs.

Bug: v8:7310
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I2fd4eac7458708d4eacb0f4871c982a567a3865e
Reviewed-on: https://chromium-review.googlesource.com/941442
Commit-Queue: Gabriel Charette <gab@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51645}

The motivation is to avoid bugs such as the one fixed in
https://chromium-review.googlesource.com/c/v8/v8/+/800270.

Bug: v8:7109
Change-Id: I82a55f4a78d289d00ae7bafe78b45d92bab07a6b
Reviewed-on: https://chromium-review.googlesource.com/800291Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49829}

(This is a reland of cb84b6f6)

This works in the ICs since compiled handlers are not shared anymore.

Bug: chromium:759734
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I3b7d6ae34bb4cfa213f679354fac56fb51bfd5ed
Reviewed-on: https://chromium-review.googlesource.com/739822Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48999}

This reverts commit cb84b6f6.

Reason for revert: <INSERT REASONING HERE>

Original change's description:
> [lazy-accessor-pairs] Don't take the fast paths if the context needs to be switched
> 
> This works in the ICs since compiled handlers are not shared anymore.
> 
> As drive-by cleanup I also removed custom code to deal with compiled handler sharing for primitive and access-checked objects.
> 
> Bug: chromium:759734
> Change-Id: Ifb394221c2398f42ea9305acc02845db6004c680
> Reviewed-on: https://chromium-review.googlesource.com/738381
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48979}

TBR=jarin@chromium.org,ishell@chromium.org,verwaest@chromium.org

Change-Id: I9b7424252cbc3f18efd6b6b5b3818651c2863f5c
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:759734
Reviewed-on: https://chromium-review.googlesource.com/739487Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48980}

This works in the ICs since compiled handlers are not shared anymore.

As drive-by cleanup I also removed custom code to deal with compiled handler sharing for primitive and access-checked objects.

Bug: chromium:759734
Change-Id: Ifb394221c2398f42ea9305acc02845db6004c680
Reviewed-on: https://chromium-review.googlesource.com/738381
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48979}

TBR=jkummerow@chromium.org

Bug: chromium:746958
Change-Id: I7500b6206c4ceb087672de5b61b7e7ad234bb425
Reviewed-on: https://chromium-review.googlesource.com/690397
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48213}

As part of J2V8 development (https://github.com/eclipsesource/J2V8),
we realized that we had a subtle bug in how Isolate scope was created
and it's lifetime managed, see:
https://github.com/eclipsesource/J2V8/issues/313.

Mentioned above bug was fixed, however, what we also noticed is that
V8 API has been constantly and slowly moving to such an API, in which
one has to pass Isolate explicitly to methods and/or constructors. We
found two more places that might have been overlooked. This contribution
adds passing of Isolate pointer explicitly to constructors of
String::Utf8Value and String::Value classes.

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng;master.tryserver.v8:v8_linux_noi18n_rel_ng
Change-Id: I61984285f152aba5ca922100cf3df913a9cb2cea
Reviewed-on: https://chromium-review.googlesource.com/593309
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47656}

In case of LAP(lazy accessor pair), the function's creation context
must be equal to the accessor holder's creation context, so this CL
changes the current context to the accessor holder's creation context.

Note that this is the second attempt after https://crrev.com/2770003002

The change from the previous attempt is to skip looking for the
object's constructor if the object itself is a function.

Also some of Blink's LAP-context-sensitive tests got updated at
https://crrev.com/c/597990 and the rest of the tests will get
temporarily disabled at https://crrev.com/c/605408 .

TBR=verwaest@chromium.org

Bug: v8:6156
Change-Id: I09709a90995d82a03996d0347e5a1d8425b5db9c
Reviewed-on: https://chromium-review.googlesource.com/563152
Commit-Queue: Yuki Shiino <yukishiino@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47572}

Revert of Set the current context to the function's context when entering to LAP. (patchset #14 id:540001 of https://codereview.chromium.org/2770003002/ )

Reason for revert:
Speculative: Seems to break webkit_unit_tests:
https://build.chromium.org/p/tryserver.v8/builders/v8_linux_blink_rel/builds/23247
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Mac/builds/11038

Original issue's description:
> Set the current context to the function's context when entering to LAP.
>
> In case of LAP(lazy accessor pair), the function's creation context
> must be equal to the accessor holder's creation context, so this CL
> changes the current context to the accessor holder's creation context.
>
> BUG=v8:6156
>
> Review-Url: https://codereview.chromium.org/2770003002
> Cr-Commit-Position: refs/heads/master@{#46406}
> Committed: https://chromium.googlesource.com/v8/v8/+/18e73287dc65452bc2f952fc005b2251fc32c15a

TBR=jochen@chromium.org,verwaest@chromium.org,mstarzinger@chromium.org,tebbi@google.com,yukishiino@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:6156

Review-Url: https://codereview.chromium.org/2973593002
Cr-Commit-Position: refs/heads/master@{#46408}

In case of LAP(lazy accessor pair), the function's creation context
must be equal to the accessor holder's creation context, so this CL
changes the current context to the accessor holder's creation context.

BUG=v8:6156

Review-Url: https://codereview.chromium.org/2770003002
Cr-Commit-Position: refs/heads/master@{#46406}

BUG=v8:6163
R=verwaest@chromium.org

Change-Id: Ieaec78c806cc3d459488a8491e77b7b5a8047079
Reviewed-on: https://chromium-review.googlesource.com/461903
Commit-Queue: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44228}

That way, we don't need to create a context-less constructor function.
Instead, we use the constructor_or_backpointer (or null) field, and
rename it to constructor_or_fti_or_backpointer so nobody is confused.

Note that technically, we still have JSFunctions without contexts, as
they're temporarily created in the deoptimizer.

BUG=v8:6084
R=dcheng@chromium.org,bmeurer@chromium.org,verwaest@chromium.org

Change-Id: I084f052533c317f2cbfb9c35e1acf40263c6257b
Reviewed-on: https://chromium-review.googlesource.com/454636
Commit-Queue: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43834}

Marking it as callable makes typeof return 'function' instead of
'object' when invoked on a remote context or object.

BUG=chromium:527190

Review-Url: https://codereview.chromium.org/2715593002
Cr-Commit-Position: refs/heads/master@{#43416}

v8 allows the embedder to specify a global template to use when
creating a new context. However, v8 does not use the supplied
template directly when creating the global proxy: it creates a
unique template for each global proxy. However, this is problematic
for remote contexts: functions cannot use strict receiver checks
with the remote context, as the global template will never match
the global proxy.

To fix this, remote contexts now also include a remote global
object in the prototype chain that is instantiated with the global
template. This mirrors the way the global proxy is configured for a
full v8 context, and allows strict receiver checks to work.

BUG=527190

Review-Url: https://codereview.chromium.org/2677653002
Cr-Commit-Position: refs/heads/master@{#43361}

BUG=693695

Review-Url: https://codereview.chromium.org/2702123002
Cr-Commit-Position: refs/heads/master@{#43309}

Remote objects don't have a creation context.

BUG=527190

Review-Url: https://codereview.chromium.org/2693203003
Cr-Commit-Position: refs/heads/master@{#43306}

TestWithIsolate and TestWithContext already instantiate the scopers.

BUG=none

Review-Url: https://codereview.chromium.org/2690303009
Cr-Commit-Position: refs/heads/master@{#43268}

https://crrev.com/2500363002 updated FunctionTemplate::HasInstance to
follow the hidden prototype chain of a global proxy to the global
object. However, remote contexts don't have a global object to check;
instead, teach the instance check knows about the conventions of
global proxy setup and have it also check the constructor's prototype.

Similarly, also teach Object::FindInstanceInPrototypeChain about the
unusual conventions for remote contexts.

BUG=527190

Review-Url: https://codereview.chromium.org/2698683003
Cr-Commit-Position: refs/heads/master@{#43263}

http://www.ecma-international.org/ecma-262/7.0/#sec-validateandapplypropertydescriptor
says that [[DefineProperty]] should return false if the property is
already defined and it's unconfigurable (exactly speaking, the condition
in the spec is more complicated, but roughly speaking, it's when the
property is unconfigurable).

BUG=chromium:670651

Review-Url: https://codereview.chromium.org/2680353004
Cr-Commit-Position: refs/heads/master@{#43080}

Without doing this, a JSMessageObject can be kept alive by the isolate, which
in turn keeps the context alive, until the message is cleared.

BUG=v8:5941

Review-Url: https://codereview.chromium.org/2675203005
Cr-Commit-Position: refs/heads/master@{#43043}

R=marja@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2682033002
Cr-Commit-Position: refs/heads/master@{#43027}