Audio is unmuted iff ChromeVox is enabled during OOBE.

BUG=328187
TEST=browser_tests:WizardControllerTest.Volume*

Review URL: https://codereview.chromium.org/138903010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247223 0039d316-1c4b-4281-b951-d872f2087c98
Improve error message display for Schema::Validate()

BUG=258339

Review URL: https://codereview.chromium.org/139853013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247224 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 247224