Parametrize Suggest polling strategy and delay. Also add a parameter

components/omnibox/search_provider.h

Index: components/omnibox/search_provider.h
diff --git a/components/omnibox/search_provider.h b/components/omnibox/search_provider.h
index 83eeaa33d8aa19a38d5c5d070c9b08bd0e97d27c..063627d75819db24298ea9723091118f282fbfd3 100644
--- a/components/omnibox/search_provider.h
+++ b/components/omnibox/search_provider.h
@@ -201,6 +201,9 @@ class SearchProvider : public BaseSearchProvider,
   // This does not update |done_|.
   void DoHistoryQuery(bool minimal_changes);
 
+  // Returns the time to delay before sending the Suggest request.
+  base::TimeDelta GetSuggestQueryDelay() const;
+
   // Determines whether an asynchronous subcomponent query should run for the
   // current input.  If so, starts it if necessary; otherwise stops it.
   // NOTE: This function does not update |done_|.  Callers must do so.
@@ -341,10 +344,6 @@ class SearchProvider : public BaseSearchProvider,
   // AnswersQueryData.
   AnswersQueryData FindAnswersPrefetchData();
 
-  // The amount of time to wait before sending a new suggest request after the
-  // previous one.  Non-const because some unittests modify this value.
-  static int kMinimumTimeBetweenSuggestQueriesMs;
-
   AutocompleteProviderListener* listener_;
 
   // The number of suggest results that haven't yet arrived. If it's greater