The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9efd9d5692ccb31a76ae6ff563475a8e5ed35653

commit 9efd9d5692ccb31a76ae6ff563475a8e5ed35653
Author: jennyz <jennyz@chromium.org>
Date: Tue Jun 07 23:24:14 2016

Disabled the failed test MediaGalleriesPlatformAppBrowserTest.GetMetadata.

BUG= 618121 
TBR=tommycli@chromium.org

Review-Url: https://codereview.chromium.org/2044593005
Cr-Commit-Position: refs/heads/master@{#398412}

[modify] https://crrev.com/9efd9d5692ccb31a76ae6ff563475a8e5ed35653/chrome/browser/extensions/api/media_galleries/media_galleries_apitest.cc

tommycli: Does this test involve the utility process? r398221 might be the culprit? The blamelist is [398218, 398227].

[17498:17498:0606/224807:INFO:CONSOLE(0)] "[SUCCESS] ImageMIMETypeOnlyTest", source: chrome-extension://nloccfejlglcppamneihhhiepjeklefg/_generated_background_page.html (0)
[17498:17498:0606/224807:INFO:CONSOLE(0)] "[SUCCESS] InvalidMultimediaFileTest", source: chrome-extension://nloccfejlglcppamneihhhiepjeklefg/_generated_background_page.html (0)
[17498:17498:0606/224807:INFO:CONSOLE(0)] "Unchecked runtime.lastError while running mediaGalleries.getMetadata: Unknown error.
    at InvalidMultimediaFileTest (chrome-extension://nloccfejlglcppamneihhhiepjeklefg/test.js:47:25)", source: chrome-extension://nloccfejlglcppamneihhhiepjeklefg/_generated_background_page.html (0)
[17498:17498:0606/224807:INFO:CONSOLE(0)] "[SUCCESS] MP3MIMETypeOnlyTest", source: chrome-extension://nloccfejlglcppamneihhhiepjeklefg/_generated_background_page.html (0)
[17498:17498:0606/224807:FATAL:extension_function.cc(502)] Check failed: !did_respond_. mediaGalleries.getMetadata
#0 0x7fe8cbfc903e base::debug::StackTrace::StackTrace()
#1 0x7fe8cc0223ac logging::LogMessage::~LogMessage()
#2 0x000004b687ae UIThreadExtensionFunction::SendResponse()
#3 0x000006973b1d extensions::MediaGalleriesGetMetadataFunction::OnSafeMediaMetadataParserDone()

thestig: I think that's a very good guess. It definitely involves the utility process.

There shouldn't have been a functional change by switching the utility process to ChannelMojo. But I'll take a look tomorrow (it's getting late here).

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e64e2962ecf525fff64e48ba3766f97eca5bdd2e

commit e64e2962ecf525fff64e48ba3766f97eca5bdd2e
Author: amistry <amistry@chromium.org>
Date: Wed Jun 15 17:57:27 2016

Always leak the Mojo parent pipe handle on child process shutdown.

In legacy Chrome-IPC, the browser uses the disconnection on the IPC
pipe as indication that the child process has died. It does this by
intentionally holding on to the parent IPC pipe in the child as the
child process exits. When the child exits, the OS closes the pipe
and the browser receives a disconnection event and assumes the child
process is dead.

When using ChannelMojo, the IPC pipe is a Mojo message pipe. In the
child, Mojo is is told to perform an orderly shutdown when the child
process is shutting down. This results in the IPC pipe being closed
before the child process dies. In this case, when the browser sees
the pipe closure, the child process may not be dead, violating the
assumption that the child is dead, which causes problems with child
termination.

To maintain existing semantics and avoid issues with child
termination, the EDK always leaks the parent pipe in the child instead
of closing it. The parent will then only see the pipe close when the
child process exits. The EDK will only leak the parent-child OS pipe
in the child process. All other pipes will be closed when Mojo is shut
down.

BUG= 618121 

Review-Url: https://codereview.chromium.org/2065453004
Cr-Commit-Position: refs/heads/master@{#399949}

[modify] https://crrev.com/e64e2962ecf525fff64e48ba3766f97eca5bdd2e/chrome/browser/extensions/api/media_galleries/media_galleries_apitest.cc
[modify] https://crrev.com/e64e2962ecf525fff64e48ba3766f97eca5bdd2e/mojo/edk/system/channel.h
[modify] https://crrev.com/e64e2962ecf525fff64e48ba3766f97eca5bdd2e/mojo/edk/system/channel_posix.cc
[modify] https://crrev.com/e64e2962ecf525fff64e48ba3766f97eca5bdd2e/mojo/edk/system/channel_win.cc
[modify] https://crrev.com/e64e2962ecf525fff64e48ba3766f97eca5bdd2e/mojo/edk/system/node_channel.cc
[modify] https://crrev.com/e64e2962ecf525fff64e48ba3766f97eca5bdd2e/mojo/edk/system/node_channel.h
[modify] https://crrev.com/e64e2962ecf525fff64e48ba3766f97eca5bdd2e/mojo/edk/system/node_controller.cc

Bulk verified