AudioPlayer: Fix the errors at the 2nd launch

This patch fixes the following bugs which causes errors at the 2nd launch:
- Typo on the background page
- An uninitialized property

BUG=343698
TEST=manually tested

Review URL: https://codereview.chromium.org/171603012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252321 0039d316-1c4b-4281-b951-d872f2087c98
AudioPlayer: Cancel the scheduled advance when the pause button clicked.

BUG=345147
TEST=manually tested

Review URL: https://codereview.chromium.org/172253002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252322 0039d316-1c4b-4281-b951-d872f2087c98
adb_profile_chrome: Add a --trace-flow flag

Add a --trace-flow flag to adb_profile_chrome for tracing IPC call
flows.

NOTRY=true

Review URL: https://codereview.chromium.org/172803002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252323 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252322
SVN changes up to revision 252323