Implement sounds for the vk.


BUG=339320

Review URL: https://codereview.chromium.org/186253003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254926 0039d316-1c4b-4281-b951-d872f2087c98
Re-inject ChromeVox to webview on spoken feedback toggle

BUG=348090
TEST=manual

Review URL: https://codereview.chromium.org/181833016

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254927 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254927