Add a java ToolbarModel.

Exposes the java WebContents out of TabBase as that will allow the
implementors of ToolbarModelDelegate to use it.

A follow up change will remove all the ToolbarModel cruft from
TabModel (once downstream is using this class instead).

BUG=331129

Review URL: https://codereview.chromium.org/122593003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242840 0039d316-1c4b-4281-b951-d872f2087c98
Fix Comment Typos in registry.h

TBR=cpu@chromium.org
BUG=

Review URL: https://codereview.chromium.org/123463002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242841 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242840
SVN changes up to revision 242841