Provide accessor for object internal properties that doesn't require debugger to be active

Provide accessor for object internal properties that doesn't require debugger to be active

Some of the DevTools' clients need to inspect JS objects without enabling debugger. This CL allows to inspect object's internal properties without enabling debugger and instantiating debug context.

Note that now debug context can be created lazily if v8::Debug::GetDebugContext is called when there is no debug listener. This is fragile and has already resulted in some subtle error. I'm going to fix that in a separate CL.

BUG=chromium:481845
LOG=Y

Committed: https://crrev.com/bdeb0de88c8cf5f2c78f261b45314138f525110d
Cr-Commit-Position: refs/heads/master@{#28362}

[yurys, 2015-05-08 10:49:49]

yurys@chromium.org changed reviewers:
+ pfeldman@chromium.org, sergeyv@chromium.org, yangguo@chromium.org

[yurys, 2015-05-08 10:50:09]

yurys@chromium.org changed reviewers:
+ kozyatinskiy@chromium.org
- sergeyv@chromium.org

[yurys, 2015-05-08 10:50:25]

The CQ bit was checked by yurys@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-05-08 10:50:33]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1126103006/1

[commit-bot: I haz the power, 2015-05-08 10:53:52]

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

[commit-bot: I haz the power, 2015-05-08 10:53:53]

Dry run: Try jobs failed on following builders:
  v8_presubmit on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_presubmit/builds/2560)

[kozy, 2015-05-08 12:36:33]

lgtm

[yurys, 2015-05-08 13:24:03]

Yang, please take a look

[yurys, 2015-05-12 06:06:57]

@yangguo, friendly ping?

[yurys, 2015-05-12 09:59:13]

Blink-side change if you're curious.

[yurys, 2015-05-12 09:59:37]

Blink-side change if you're curious: https://codereview.chromium.org/1141553003/

[Yang, 2015-05-12 11:36:41]

https://codereview.chromium.org/1126103006/diff/1/src/runtime/runtime-debug.cc
File src/runtime/runtime-debug.cc (right):

https://codereview.chromium.org/1126103006/diff/1/src/runtime/runtime-debug.c...
src/runtime/runtime-debug.cc:223: result->set(0,
*factory->NewStringFromAsciiChecked("[[PromiseStatus]]"));
FYI this allocates a lot of strings, as this is not internalized/canonicalized.

https://codereview.chromium.org/1126103006/diff/1/src/runtime/runtime-debug.c...
src/runtime/runtime-debug.cc:249: return isolate->ThrowIllegalOperation();
I don't think this can work. If we get here, there is already a pending
exception. Throwing again would hit an assertion in Isolate::Throw.

[yurys, 2015-05-12 11:50:39]

https://codereview.chromium.org/1126103006/diff/1/src/runtime/runtime-debug.cc
File src/runtime/runtime-debug.cc (right):

https://codereview.chromium.org/1126103006/diff/1/src/runtime/runtime-debug.c...
src/runtime/runtime-debug.cc:223: result->set(0,
*factory->NewStringFromAsciiChecked("[[PromiseStatus]]"));
On 2015/05/12 11:36:41, Yang wrote:
> FYI this allocates a lot of strings, as this is not
internalized/canonicalized.

This code is not performance critical, we can optimize it later should we
encounter any problems. I was hesitant to allocate it as internalized strings
for that reason. I don't know what the current guidelines regarding string
allocation, do you think it'd be more appropriate to internalize these strings?

https://codereview.chromium.org/1126103006/diff/1/src/runtime/runtime-debug.c...
src/runtime/runtime-debug.cc:249: return isolate->ThrowIllegalOperation();
On 2015/05/12 11:36:40, Yang wrote:
> I don't think this can work. If we get here, there is already a pending
> exception. Throwing again would hit an assertion in Isolate::Throw.

Done.

[Yang, 2015-05-12 11:53:04]

lgtm if comment addressed.

https://codereview.chromium.org/1126103006/diff/20001/src/runtime/runtime-deb...
File src/runtime/runtime-debug.cc (right):

https://codereview.chromium.org/1126103006/diff/20001/src/runtime/runtime-deb...
src/runtime/runtime-debug.cc:248: if (!Runtime::GetInternalProperties(isolate,
obj).ToHandle(&result)) {
Please use RETURN_FAILURE_ON_EXCEPTION here.

[yurys, 2015-05-12 12:07:47]

https://codereview.chromium.org/1126103006/diff/20001/src/runtime/runtime-deb...
File src/runtime/runtime-debug.cc (right):

https://codereview.chromium.org/1126103006/diff/20001/src/runtime/runtime-deb...
src/runtime/runtime-debug.cc:248: if (!Runtime::GetInternalProperties(isolate,
obj).ToHandle(&result)) {
On 2015/05/12 11:53:04, Yang wrote:
> Please use RETURN_FAILURE_ON_EXCEPTION here.

Done. Changed this code to use ASSIGN_RETURN_FAILURE_ON_EXCEPTION.

[yurys, 2015-05-12 12:07:55]

The CQ bit was checked by yurys@chromium.org

[yurys, 2015-05-12 12:07:55]

The patchset sent to the CQ was uploaded after l-g-t-m from
kozyatinskiy@chromium.org, yangguo@chromium.org
Link to the patchset: https://codereview.chromium.org/1126103006/#ps40001
(title: " ")

[commit-bot: I haz the power, 2015-05-12 12:08:04]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1126103006/40001

[commit-bot: I haz the power, 2015-05-12 12:38:22]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-05-12 12:38:40]

Patchset 3 (id:??) landed as
https://crrev.com/bdeb0de88c8cf5f2c78f261b45314138f525110d
Cr-Commit-Position: refs/heads/master@{#28362}

[Yang, 2015-05-12 13:03:32]

A revert of this CL (patchset #3 id:40001) has been created in
https://codereview.chromium.org/1133243002/ by yangguo@chromium.org.

The reason for reverting is: GC mole issues:
https://chromegw.corp.google.com/i/client.v8/builders/V8%20Linux%20-%20gcmole....