add suppression for UNINIT READ at content::BrowserAccessibilityManagerWin
BUG=349128
TBR=dmazzoni@chromium.org,bruening@chrimum.org

Review URL: https://codereview.chromium.org/186193007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254842 0039d316-1c4b-4281-b951-d872f2087c98
Use NULL for ExtensionKeyBindingRegistry::Delegate for app windows.

This avoids forcing AppWindow to be a delegate that does nothing.

Review URL: https://codereview.chromium.org/180633012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254843 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254843