Fixed strict mode violation in history

 Bug: 3257747
 Fixes a strict mode violation in BrowserHistoryPage. onPrepareOptionsMenu
 is doing a query on the UI thread to determine if it should show clear
 history or not. Fixed by having it ask the adapter, which is loaded async

Change-Id: I12338987098d093e63f1944f2a1458ad962d0c78
1 file changed