base: Add ScopedJavaLocalFrame class.

base: Add ScopedJavaLocalFrame class.

This class can be used to create a local reference frame. A local
reference frame ensures that some amount of local references can
be created and forces all references created in the frame to be
releases when exiting the frame.

BUG=360069
TBR=darin

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=262273

[reveman, 2014-04-04 16:18:31]

https://codereview.chromium.org/225283008/diff/1/content/app/android/child_pr...
File content/app/android/child_process_service.cc (right):

https://codereview.chromium.org/225283008/diff/1/content/app/android/child_pr...
content/app/android/child_process_service.cc:99:
base::android::ScopedJavaLocalFrame scoped_local_reference_frame(env);
We might want to land this separately from the base/android change but included
it here for now as an example of how it can be used.

[no sievers, 2014-04-04 20:32:11]

LGTM w/nits

https://codereview.chromium.org/225283008/diff/1/base/android/scoped_java_ref.cc
File base/android/scoped_java_ref.cc (right):

https://codereview.chromium.org/225283008/diff/1/base/android/scoped_java_ref...
base/android/scoped_java_ref.cc:83: env_->PushLocalFrame(capacity);
Might want to DCHECK() that this returns 0, esp. if you take user values here.

https://codereview.chromium.org/225283008/diff/1/base/android/scoped_java_ref.h
File base/android/scoped_java_ref.h (right):

https://codereview.chromium.org/225283008/diff/1/base/android/scoped_java_ref...
base/android/scoped_java_ref.h:163: JNIEnv* env_;
DISALLOW_COPY_AND_ASSIGN

[reveman, 2014-04-04 21:07:07]

https://codereview.chromium.org/225283008/diff/1/base/android/scoped_java_ref.cc
File base/android/scoped_java_ref.cc (right):

https://codereview.chromium.org/225283008/diff/1/base/android/scoped_java_ref...
base/android/scoped_java_ref.cc:83: env_->PushLocalFrame(capacity);
On 2014/04/04 20:32:11, sievers wrote:
> Might want to DCHECK() that this returns 0, esp. if you take user values here.

Done.

https://codereview.chromium.org/225283008/diff/1/base/android/scoped_java_ref.h
File base/android/scoped_java_ref.h (right):

https://codereview.chromium.org/225283008/diff/1/base/android/scoped_java_ref...
base/android/scoped_java_ref.h:163: JNIEnv* env_;
On 2014/04/04 20:32:11, sievers wrote:
> DISALLOW_COPY_AND_ASSIGN

Done.

[reveman, 2014-04-04 21:12:44]

+bulach for base/android
+darin for mojo

[bulach, 2014-04-07 15:51:29]

lgtm % nits, thanks!

https://codereview.chromium.org/225283008/diff/40001/base/android/scoped_java...
File base/android/scoped_java_ref.cc (right):

https://codereview.chromium.org/225283008/diff/40001/base/android/scoped_java...
base/android/scoped_java_ref.cc:77:
ScopedJavaLocalFrame::ScopedJavaLocalFrame(JNIEnv* env) : env_(env) {
ditto, probably best moving to the top..

https://codereview.chromium.org/225283008/diff/40001/base/android/scoped_java...
File base/android/scoped_java_ref.h (right):

https://codereview.chromium.org/225283008/diff/40001/base/android/scoped_java...
base/android/scoped_java_ref.h:154: class BASE_EXPORT ScopedJavaLocalFrame {
nit: may I ask to move this one either as the first one on the top of this file?
:) reason being that LocalRef and GlobalRef are somewhat related...

[reveman, 2014-04-07 17:38:29]

https://codereview.chromium.org/225283008/diff/40001/base/android/scoped_java...
File base/android/scoped_java_ref.cc (right):

https://codereview.chromium.org/225283008/diff/40001/base/android/scoped_java...
base/android/scoped_java_ref.cc:77:
ScopedJavaLocalFrame::ScopedJavaLocalFrame(JNIEnv* env) : env_(env) {
On 2014/04/07 15:51:29, bulach_ooo_14apr wrote:
> ditto, probably best moving to the top..

Done.

https://codereview.chromium.org/225283008/diff/40001/base/android/scoped_java...
File base/android/scoped_java_ref.h (right):

https://codereview.chromium.org/225283008/diff/40001/base/android/scoped_java...
base/android/scoped_java_ref.h:154: class BASE_EXPORT ScopedJavaLocalFrame {
On 2014/04/07 15:51:29, bulach_ooo_14apr wrote:
> nit: may I ask to move this one either as the first one on the top of this
file?
> :) reason being that LocalRef and GlobalRef are somewhat related...

Done.

[reveman, 2014-04-07 17:39:20]

The CQ bit was checked by reveman@chromium.org

[commit-bot: I haz the power, 2014-04-07 17:39:58]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/reveman@chromium.org/225283008/60001

[reveman, 2014-04-07 21:49:56]

The CQ bit was checked by reveman@chromium.org

[commit-bot: I haz the power, 2014-04-07 21:50:57]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/reveman@chromium.org/225283008/80001

[commit-bot: I haz the power, 2014-04-08 01:01:54]

Change committed as 262273