Change Context::New not create persistent handles.

Change Context::New to not create persistent handles.

This moves the responsibility of putting a new context into a persistent
handle to the embedder. Also it removes one API function where the copy
constructor for persistent handles is needed.

R=svenpanne@chromium.org

Committed: http://code.google.com/p/v8/source/detail?r=14203

[Michael Starzinger, 2013-04-08 14:23:19]

The cctests are not yet adapted, this is a huge chunk of work and I wanted to
sync that with you to not cause any merge conflicts for you.

[Sven Panne, 2013-04-09 07:08:33]

https://codereview.chromium.org/13799003/diff/1/include/v8.h
File include/v8.h (right):

https://codereview.chromium.org/13799003/diff/1/include/v8.h#newcode3891
include/v8.h:3891: /** Deprecated. Use Isolate version instead. */
Perhaps add an explicit TODO for inserting V8_DEPRECATED, we have this already
at other places.

https://codereview.chromium.org/13799003/diff/1/src/bootstrapper.cc
File src/bootstrapper.cc (right):

https://codereview.chromium.org/13799003/diff/1/src/bootstrapper.cc#newcode308
src/bootstrapper.cc:308: if (InstallExtensions(env, extensions)) {
Merge the "if"s, move the last "return" to an "else" branch, swap the "if"
branches by inverting the condition, drop the "else" again. :-) This makes the
normal control flow clearer, with the exceptional cases bailing out early, which
is a good idea:
http://www.refactoring.com/catalog/replaceNestedConditionalWithGuardClauses.html

https://codereview.chromium.org/13799003/diff/1/src/debug.cc
File src/debug.cc (right):

https://codereview.chromium.org/13799003/diff/1/src/debug.cc#newcode878
src/debug.cc:878: debug_context_ = Handle<Context>::cast(
I don't fully understand why this is necessary...

[Michael Starzinger, 2013-04-09 13:29:18]

Comments addressed. I still need to adapt test cases and will do so after
rebasing on the following dependent CL.

https://codereview.chromium.org/13483017/

https://codereview.chromium.org/13799003/diff/1/include/v8.h
File include/v8.h (right):

https://codereview.chromium.org/13799003/diff/1/include/v8.h#newcode3891
include/v8.h:3891: /** Deprecated. Use Isolate version instead. */
On 2013/04/09 07:08:33, Sven Panne wrote:
> Perhaps add an explicit TODO for inserting V8_DEPRECATED, we have this already
> at other places.

Done.

https://codereview.chromium.org/13799003/diff/1/src/bootstrapper.cc
File src/bootstrapper.cc (right):

https://codereview.chromium.org/13799003/diff/1/src/bootstrapper.cc#newcode308
src/bootstrapper.cc:308: if (InstallExtensions(env, extensions)) {
On 2013/04/09 07:08:33, Sven Panne wrote:
> Merge the "if"s, move the last "return" to an "else" branch, swap the "if"
> branches by inverting the condition, drop the "else" again. :-) This makes the
> normal control flow clearer, with the exceptional cases bailing out early,
which
> is a good idea:
>
http://www.refactoring.com/catalog/replaceNestedConditionalWithGuardClauses.html

Done.

https://codereview.chromium.org/13799003/diff/1/src/debug.cc
File src/debug.cc (right):

https://codereview.chromium.org/13799003/diff/1/src/debug.cc#newcode878
src/debug.cc:878: debug_context_ = Handle<Context>::cast(
On 2013/04/09 07:08:33, Sven Panne wrote:
> I don't fully understand why this is necessary...

As discussed offline, this creates a persistent handle for the newly created
debug context so that it can be put into a static (per-isolate) variable.

[Sven Panne, 2013-04-09 13:52:28]

LGTM if the "return" is added.

https://codereview.chromium.org/13799003/diff/9001/src/bootstrapper.cc
File src/bootstrapper.cc (right):

https://codereview.chromium.org/13799003/diff/9001/src/bootstrapper.cc#newcod...
src/bootstrapper.cc:307: if (env.is_null() || !InstallExtensions(env,
extensions)) Handle<Context>();
A "return" might be helpful here... ;-)

[Michael Starzinger, 2013-04-10 09:01:11]

Comments addressed. Tests adapted.

https://codereview.chromium.org/13799003/diff/9001/src/bootstrapper.cc
File src/bootstrapper.cc (right):

https://codereview.chromium.org/13799003/diff/9001/src/bootstrapper.cc#newcod...
src/bootstrapper.cc:307: if (env.is_null() || !InstallExtensions(env,
extensions)) Handle<Context>();
On 2013/04/09 13:52:28, Sven Panne wrote:
> A "return" might be helpful here... ;-)

Done. Yeah, a "return" might come in handy here. :P

[Michael Starzinger, 2013-04-10 09:34:50]

Committed patchset #4 manually as r14203 (presubmit successful).