Adds a new "AccessibilityAlertInfo" event and removes AccessibilityManager::Speak and AccessibilityManager::MaybeSpeak.

BUG=316710
TEST=Sign in and observe output in both braille and speech.

Review URL: https://codereview.chromium.org/66583007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234876 0039d316-1c4b-4281-b951-d872f2087c98
Update V8 to version 3.23.3.1.

TBR=jkummerow@chromium.org
BUG=

Review URL: https://codereview.chromium.org/71483002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234877 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234878 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 234877
SVN changes up to revision 234878