Restoring notifications on startup without making a server poll.

BUG=164227
TEST=Receive cards. Close Chrome process. Disconnect from network. Start Chrome. Cards should be shown on startup.
Alternatively: Receive cards. In less than 5 minutes: Close Chrome process, start it, make sure cards are shown and the devtools log doesn't show a server request.

Review URL: https://codereview.chromium.org/27030012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228856 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228856
Refactor HistoryDataStore into DictionaryDataStore+HistoryDataStore.
Separate out the part that writes the dictionary to a file store into a separate class, DictionaryDataStore.

R=xiyuan@chromium.org
BUG=None.
TEST=Unit tests pass, search cross-session functionality works correctly.

Review URL: https://codereview.chromium.org/26179007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228857 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228857
Update dock size when auto-hiding shelf

BUG=298210
TEST=ash_unittests --gtest_filter=*AttachOneAutoHideShelf*

Review URL: https://codereview.chromium.org/26662002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228858 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228858