Updates Object.prototype.toString() to use algorithm described in harmony drafts.

Currently, the behaviour is essentially the same as ES262's version, however this changes when internal structures
such as Promise make use of symbolToStringTag (as they are supposed to, see v8:3241), and changes further once
Symbol.toStringTag is exposed publicly.

BUG=v8:3241, v8:3502
LOG=N
R=dslomov@chromium.org

Review URL: https://codereview.chromium.org/546803003

Patch from Caitlin Potter <caitpotter88@gmail.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24783 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=jarin@chromium.org

Review URL: https://codereview.chromium.org/654583004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24782 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/669683002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24781 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/667953002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24780 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=jarin@chromium.org, bmeurer@chromium.org

BUG=

Review URL: https://codereview.chromium.org/663333003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24779 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=jarin@chromium.org
BUG=

Review URL: https://codereview.chromium.org/671703003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24778 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/640203004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24777 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

(I'm puzzled why GCC did not report this error.)

TBR=bmeurer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/669733007

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24776 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

version of the keyed load stub (https://code.google.com/p/v8/source/detail?r=24661),
I allowed polymorphism between string and non-string types in the IC. Before, the
IC would go generic.

Then, at crankshaft time, we special case when we only saw strings. The error
here is that crankshaft can't emit code that handles polymorphism between string
and non-string types. The choice is either to get that to happen (I don't deem
this necessary from a performance point of view, an IC with such type feedback
before would have gone generic), or simply check for the case of "polymorphic
with some string maps" and require crankshaft to go generic. I'll do the latter.

BUG=425519
LOG=N
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/667923004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24775 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=bmeurer@chromium.org
BUG=421634
LOG=N

Review URL: https://codereview.chromium.org/667703002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24774 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=none
R=ulan@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/671513006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24773 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=bmeurer@chromium.org

BUG=

Review URL: https://codereview.chromium.org/665893006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24771 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TEST=unittests
R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/666723005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24770 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

This will allow us to move expressions from one function to another, for
example when the parser determines that a given cover grammar instance
is actually the default value initializer for an arrow function.

This is a re-land of https://codereview.chromium.org/636403003/ with a
fix for the arm64 code generator.

R=svenpanne@chromium.org
BUG=

Review URL: https://codereview.chromium.org/663373003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24769 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=rossberg@chromium.org

Review URL: https://codereview.chromium.org/670623003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24768 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/670703002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24767 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TEST=mjsunit/external-array
BUG=
R=dslomov@chromium.org

Review URL: https://codereview.chromium.org/667113002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24766 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=yangguo@chromium.org

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24765 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/667933002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24764 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=bmeurer@chromium.org
TBR=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/652403003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24763 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

This reverts r24757, which breaks the ARM64 simulator build.
Simple repro:

   out/arm64.debug/d8 -e 'eval("(function(){ const x; var x; })")'

TBR=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/652543006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24762 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=ishell@chromium.org

Review URL: https://codereview.chromium.org/663033004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24761 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

LOG=N
BUG=chromium:425146
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/665243002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24760 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
TBR=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/663343002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24759 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

It is faster to test for smi zero from generated code.

BUG=
R=erikcorry@chromium.org

Review URL: https://codereview.chromium.org/637253004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24758 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

This will allow us to move expressions from one function to another, for
example when the parser determines that a given cover grammar instance
is actually the default value initializer for an arrow function.

R=svenpanne@chromium.org, marja@chromium.org
BUG=

Review URL: https://codereview.chromium.org/636403003

Patch from Andy Wingo <wingo@igalia.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24757 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

port r24732.

original commit message:

  vector-based ICs did not update type feedback counts correctly.

BUG=
R=weiliang.lin@intel.com

Review URL: https://codereview.chromium.org/669823002

Patch from Chunyang Dai <chunyang.dai@intel.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24756 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Basically a follow-up to https://codereview.chromium.org/667573005/.

LOG=y
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/670673002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24755 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=bmeurer@chromium.org

BUG=

Review URL: https://codereview.chromium.org/668883002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24754 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=bmeurer@chromium.org

BUG=

Review URL: https://codereview.chromium.org/664123002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24753 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=vogelheim@chromium.org

Review URL: https://codereview.chromium.org/670433003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24752 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/667573005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24751 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Port r24732 (83e975b)

BUG=v8:3605
LOG=N
R=paul.lind@imgtec.com

Review URL: https://codereview.chromium.org/670543002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24746 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=ulan@chromium.org

Review URL: https://codereview.chromium.org/651683003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24745 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/665883002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24744 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=rossberg@chromium.org
BUG=v8:3640
LOG=N

Review URL: https://codereview.chromium.org/642233003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24743 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/648643003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24742 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=ishell@chromium.org

Review URL: https://codereview.chromium.org/668663002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24741 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=dslomov@chromium.org
BUG=

Review URL: https://codereview.chromium.org/639373005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24740 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/663043003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24739 ce2b1a6d-e550-0410-aec6-3dcde31c8c00