Implement chrome.browserAction.openPopup API.
https://docs.google.com/a/google.com/document/d/10NtNR0R77izXUd3kWWvrIzyqIJ2ZRP8jkkzuHw7mNUY/edit

BUG=305744

Review URL: https://codereview.chromium.org/25305002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229777 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229777
Blink roll 160056:160072

http://build.chromium.org/f/chromium/perf/dashboard/ui/changelog_blink.html?url=/trunk&range=160057:160072&mode=html
TBR=
BUG=

Review URL: https://codereview.chromium.org/30133004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229778 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229779 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229778
SVN changes up to revision 229779