GitLab

 * Fix a regression so that once again the time range selector combo-box is in focus initially.
 * Clean up the code that determines which controls should be enabled/disabled/hidden on the dialog.
 * Reduce the number of controls that flicker (i.e. change state from disabled->enabled visibly) on opening the dialog in the most likely use-case, i.e., instead of starting with everything disabled, only have the commit button initially disabled.
 * Fix a regression so that once again some checkboxes can be disabled by policies. (I think this was also broken.)

BUG=365206

Review URL: https://codereview.chromium.org/275483005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@274090 0039d316-1c4b-4281-b951-d872f2087c98