devtools: Fix crash when WebContents is deleted by a message handler

devtools: Fix crash when WebContents is deleted by a message handler

If a DevTools message handler deletes the WebContents which originated
the message, we previously tried to access a member of an already-freed
FrameHostHolder.

TEST=headless_browsertests --gtest_filter=HeadlessBrowserContextIsolationTest.RunAsyncTest

Committed: https://crrev.com/2ce98a25d03dadf0434e885fc36dd976ea7d7519
Cr-Commit-Position: refs/heads/master@{#439879}

[Sami, 2016-12-20 17:48:07]

Description was changed from

==========
devtools: Fix crash when WebContents is deleted by a message handler

If a DevTools message handler deletes the WebContents which originated
the message, we previously tried to access a member of an already-freed
FrameHostHolder.

TEST=headless_browsertests
--gtest_filter=HeadlessBrowserContextIsolationTest.RunAsyncTest
==========

to

==========
devtools: Fix crash when WebContents is deleted by a message handler

If a DevTools message handler deletes the WebContents which originated
the message, we previously tried to access a member of an already-freed
FrameHostHolder.

TEST=headless_browsertests
--gtest_filter=HeadlessBrowserContextIsolationTest.RunAsyncTest
==========

[Sami, 2016-12-20 17:48:08]

skyostil@chromium.org changed reviewers:
+ dgozman@chromium.org

[Sami, 2016-12-20 17:48:15]

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

[commit-bot: I haz the power, 2016-12-20 17:48:36]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Sami, 2016-12-20 18:05:01]

+jam@ FYI, I think this one snuck in via
https://codereview.chromium.org/2585053002.

[dgozman, 2016-12-20 18:35:43]

lgtm, thanks for the fix.

[Sami, 2016-12-20 18:41:48]

The CQ bit was unchecked by skyostil@chromium.org

[Sami, 2016-12-20 18:41:54]

The CQ bit was checked by skyostil@chromium.org

[commit-bot: I haz the power, 2016-12-20 18:42:16]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-20 20:24:33]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1482259314635960, "parent_rev":
"579a348c2c1a59c26d898e6bbd930778bf0d3aed", "commit_rev":
"d6d2feedfd0d580ad47603b97229898a7370339d"}

[commit-bot: I haz the power, 2016-12-20 20:25:05]

Description was changed from

==========
devtools: Fix crash when WebContents is deleted by a message handler

If a DevTools message handler deletes the WebContents which originated
the message, we previously tried to access a member of an already-freed
FrameHostHolder.

TEST=headless_browsertests
--gtest_filter=HeadlessBrowserContextIsolationTest.RunAsyncTest
==========

to

==========
devtools: Fix crash when WebContents is deleted by a message handler

If a DevTools message handler deletes the WebContents which originated
the message, we previously tried to access a member of an already-freed
FrameHostHolder.

TEST=headless_browsertests
--gtest_filter=HeadlessBrowserContextIsolationTest.RunAsyncTest

Review-Url: https://codereview.chromium.org/2597453002
==========

[commit-bot: I haz the power, 2016-12-20 20:25:06]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-12-20 20:29:10]

Description was changed from

==========
devtools: Fix crash when WebContents is deleted by a message handler

If a DevTools message handler deletes the WebContents which originated
the message, we previously tried to access a member of an already-freed
FrameHostHolder.

TEST=headless_browsertests
--gtest_filter=HeadlessBrowserContextIsolationTest.RunAsyncTest

Review-Url: https://codereview.chromium.org/2597453002
==========

to

==========
devtools: Fix crash when WebContents is deleted by a message handler

If a DevTools message handler deletes the WebContents which originated
the message, we previously tried to access a member of an already-freed
FrameHostHolder.

TEST=headless_browsertests
--gtest_filter=HeadlessBrowserContextIsolationTest.RunAsyncTest

Committed: https://crrev.com/2ce98a25d03dadf0434e885fc36dd976ea7d7519
Cr-Commit-Position: refs/heads/master@{#439879}
==========

[commit-bot: I haz the power, 2016-12-20 20:29:11]

Patchset 1 (id:??) landed as
https://crrev.com/2ce98a25d03dadf0434e885fc36dd976ea7d7519
Cr-Commit-Position: refs/heads/master@{#439879}