Remove ActiveDOMObject::willStop, and introduce WorkerGlobalScope::TerminationObserver.

Remove ActiveDOMObject::willStop, and introduce WorkerGlobalScope::TerminationObserver.

ActiveDOMObject::willStop is called in the main thread, and it's very confusing
because other functions are called in ActiveDOMObject's context thread.

Only synchronous Web SQL Database needs willStop.  This CL inroduces a dedicated
interface to notify termination request to a Worker, and DatabaseContext
implements it.

BUG=352621
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=172357

[tkent, 2014-04-23 08:34:50]

Would you review this again please?

[haraken, 2014-04-23 08:53:54]

LGTM.

https://codereview.chromium.org/248523003/diff/1/Source/core/workers/WorkerGl...
File Source/core/workers/WorkerGlobalScope.cpp (right):

https://codereview.chromium.org/248523003/diff/1/Source/core/workers/WorkerGl...
Source/core/workers/WorkerGlobalScope.cpp:203: {

Shall we add ASSERT(isMainThread()) ?

[sof, 2014-04-23 09:04:25]

https://codereview.chromium.org/248523003/diff/1/Source/modules/webdatabase/D...
File Source/modules/webdatabase/DatabaseContext.cpp (right):

https://codereview.chromium.org/248523003/diff/1/Source/modules/webdatabase/D...
Source/modules/webdatabase/DatabaseContext.cpp:134: if
(executionContext()->isWorkerGlobalScope())
Clarifying question: is this access of the WorkerGlobalScope safe in the Oilpan
case?

[tkent, 2014-04-23 09:13:35]

https://codereview.chromium.org/248523003/diff/1/Source/core/workers/WorkerGl...
File Source/core/workers/WorkerGlobalScope.cpp (right):

https://codereview.chromium.org/248523003/diff/1/Source/core/workers/WorkerGl...
Source/core/workers/WorkerGlobalScope.cpp:203: {
On 2014/04/23 08:53:55, haraken wrote:
> 
> Shall we add ASSERT(isMainThread()) ?

I'm not 100% sure this is always in the main thread.

https://codereview.chromium.org/248523003/diff/1/Source/modules/webdatabase/D...
File Source/modules/webdatabase/DatabaseContext.cpp (right):

https://codereview.chromium.org/248523003/diff/1/Source/modules/webdatabase/D...
Source/modules/webdatabase/DatabaseContext.cpp:134: if
(executionContext()->isWorkerGlobalScope())
On 2014/04/23 09:04:26, sof wrote:
> Clarifying question: is this access of the WorkerGlobalScope safe in the
Oilpan
> case?

Yes, it's safe.

[tkent, 2014-04-23 09:13:47]

The CQ bit was checked by tkent@chromium.org

[commit-bot: I haz the power, 2014-04-23 09:14:20]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tkent@chromium.org/248523003/1

[haraken, 2014-04-23 09:17:36]

https://codereview.chromium.org/248523003/diff/1/Source/core/workers/WorkerGl...
File Source/core/workers/WorkerGlobalScope.h (right):

https://codereview.chromium.org/248523003/diff/1/Source/core/workers/WorkerGl...
Source/core/workers/WorkerGlobalScope.h:89: // The function is called in the
main thread.

Given that this is not always called from the main thread, shall we drop this
comment?

[commit-bot: I haz the power, 2014-04-23 09:19:19]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-04-23 09:19:20]

Try jobs failed on following builders:
  tryserver.blink on linux_blink_dbg
  tryserver.blink on linux_blink_rel

[tkent, 2014-04-23 09:24:52]

https://codereview.chromium.org/248523003/diff/1/Source/core/workers/WorkerGl...
File Source/core/workers/WorkerGlobalScope.h (right):

https://codereview.chromium.org/248523003/diff/1/Source/core/workers/WorkerGl...
Source/core/workers/WorkerGlobalScope.h:89: // The function is called in the
main thread.
On 2014/04/23 09:17:36, haraken wrote:
> 
> Given that this is not always called from the main thread, shall we drop this
> comment?

Updated the comment.

[tkent, 2014-04-23 09:24:57]

The CQ bit was checked by tkent@chromium.org

[commit-bot: I haz the power, 2014-04-23 09:25:08]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tkent@chromium.org/248523003/20001

[commit-bot: I haz the power, 2014-04-23 10:31:42]

Change committed as 172357