Replace HistoryQuickProvider protobuf-based caching with an SQLite-based database.

chrome/browser/autocomplete/history_quick_provider.cc

Index: chrome/browser/autocomplete/history_quick_provider.cc
===================================================================
--- chrome/browser/autocomplete/history_quick_provider.cc	(revision 151481)
+++ chrome/browser/autocomplete/history_quick_provider.cc	(working copy)
@@ -147,8 +147,13 @@
   }
 }
 
-// TODO(mrossetti): Implement this function. (Will happen in next CL.)
-void HistoryQuickProvider::DeleteMatch(const AutocompleteMatch& match) {}
+void HistoryQuickProvider::DeleteMatch(const AutocompleteMatch& match) {
+  DCHECK(match.deletable);
+  DCHECK(match.destination_url.is_valid());
+  // Delete the match from the InMemoryURLIndex.
+  GetIndex()->DeleteURL(match.destination_url);
+  DeleteMatchFromMatches(match);
+}
 
 HistoryQuickProvider::~HistoryQuickProvider() {}