Add additional histogram events for prefetches to the prerender local

chrome/browser/prerender/prerender_local_predictor.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_PRERENDER_PRERENDER_LOCAL_PREDICTOR_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_LOCAL_PREDICTOR_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 124 matching lines @@
     EVENT_CONTINUE_PRERENDER_CHECK_EXAMINE_NEXT_URL_NOT_SKIPPED = 83,
     EVENT_PRERENDER_SERVICE_RETURNED_HINTING_CANDIDATES = 84,
     EVENT_NAMESPACE_MISMATCH_MERGE_RESULT_NAMESPACE_NOT_ALIAS = 85,
     EVENT_TAB_HELPER_URL_SEEN_MATCH_ENTRY = 86,
     EVENT_TAB_HELPER_URL_SEEN_MATCH_BROWSER_NAVIGATE = 87,
     EVENT_TAB_HELPER_URL_SEEN_NAMESPACE_MATCH_ENTRY = 88,
     EVENT_TAB_HELPER_URL_SEEN_NAMESPACE_MATCH_BROWSER_NAVIGATE = 89,
     EVENT_PREFETCH_LIST_ADDED = 90,
     EVENT_PREFETCH_LIST_SEEN_TABCONTENTS = 91,
     EVENT_PREFETCH_LIST_SEEN_HISTORY = 92,
+    EVENT_ISSUE_PRERENDER_CALLED = 93,
+    EVENT_ISSUE_PRERENDER_PREFETCH_ENABLED = 94,
+    EVENT_ISSUE_PRERENDER_PREFETCH_ISSUED = 95,
     EVENT_MAX_VALUE
   };
 
   // A PrerenderLocalPredictor is owned by the PrerenderManager specified
   // in the constructor.  It will be destoryed at the time its owning
   // PrerenderManager is destroyed.
   explicit PrerenderLocalPredictor(PrerenderManager* prerender_manager);
   virtual ~PrerenderLocalPredictor();
 
   void Shutdown();
@@ skipping 78 matching lines @@
   base::WeakPtrFactory<PrerenderLocalPredictor> weak_factory_;
 
   scoped_ptr<PrefetchList> prefetch_list_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderLocalPredictor);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_LOCAL_PREDICTOR_H_