Simplify the way to initialize context

Simplify the way to initialize context

(Background: This is a preparation CL for making DOMWrapperWorld::current() callable from anywhere.)

Currently, when we initialize a context, we need to call the following things in a proper order.

- V8PerContextDataHolder::install()
- V8PerContextData::create()
- V8PerContextData::init()
- gin::ContextHolder()
- gin::ContextHolder::SetContext()

However, this is more complicated than necessary. This CL refactors code so that we just need to call V8PerContextData::create() when initializing a context.

Specifically, this CL does the following refactoring:

- Move gin::ContextHolder from V8WindowShell/WorkerScriptController to V8PerContextData.
- Remove V8_STORE_PRIMORDIAL macro.
- Move the contents of V8PerContextData::init() to V8PerContextData's constructor.

BUG=341032
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=168260

[haraken, 2014-02-28 11:14:05]

PTAL

Probably this CL is doing multiple things. I'm happy to split the CL into pieces
if you like.

https://codereview.chromium.org/180773003/diff/1/Source/bindings/v8/ScriptPro...
File Source/bindings/v8/ScriptPromiseResolverTest.cpp (right):

https://codereview.chromium.org/180773003/diff/1/Source/bindings/v8/ScriptPro...
Source/bindings/v8/ScriptPromiseResolverTest.cpp:58: // FIXME: Create a new
world and pass it to V8PerContextData.

I'll address this in a follow-up CL. Passing 0 doesn't change any existing test
behavior because DOMWrapperWorld::current() has been returning 0.

https://codereview.chromium.org/180773003/diff/1/Source/bindings/v8/V8PerCont...
File Source/bindings/v8/V8PerContextData.cpp (left):

https://codereview.chromium.org/180773003/diff/1/Source/bindings/v8/V8PerCont...
Source/bindings/v8/V8PerContextData.cpp:61: #define V8_STORE_PRIMORDIAL(name,
Name) \

This macro is used by only one place, so I inlined the macro into
V8PerContextData's constructor.

https://codereview.chromium.org/180773003/diff/1/Source/bindings/v8/V8PerCont...
Source/bindings/v8/V8PerContextData.cpp:76: bool V8PerContextData::init()

In reality, init() should not return false. Thus I inlined init() into
V8PerContextData's constructor.

[dcarney, 2014-02-28 11:32:05]

lgtm

[haraken, 2014-03-03 00:49:56]

Nit: I noticed that V8PerContextDataHolder is still necessary. At first I
thought that the lifetime of V8PerContextData and V8PerContextDataHolder are the
same, but it isn't.

- V8PerContextDataHolder should be kept alive as long as v8::Context is alive.
- V8PerContextData should be kept alive as long as
V8WindowShell/WorkerScriptController retains it.

Thus I reverted the V8PerContextDataHolder part back to the CL.

Landing.

[haraken, 2014-03-03 00:50:01]

The CQ bit was checked by haraken@chromium.org

[commit-bot: I haz the power, 2014-03-03 00:50:17]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/haraken@chromium.org/180773003/20001

[commit-bot: I haz the power, 2014-03-03 03:45:45]

Change committed as 168260