Use stricter type checking in UMA_HISTOGRAM_ENUMERATION

chrome/browser/prerender/prerender_link_manager.cc

 // 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.
 
 #include "chrome/browser/prerender/prerender_link_manager.h"
 
 #include <functional>
 #include <limits>
 #include <memory>
 #include <set>
@@ skipping 56 matching lines @@
 enum RelTypeHistogramEnum {
   RelTypeHistogramEnumNone = 0,
   RelTypeHistogramEnumPrerender = PrerenderRelTypePrerender,
   RelTypeHistogramEnumNext = PrerenderRelTypeNext,
   RelTypeHistogramEnumPrerenderAndNext =
       PrerenderRelTypePrerender | PrerenderRelTypeNext,
   RelTypeHistogramEnumMax,
 };
 
 void RecordLinkManagerAdded(const uint32_t rel_types) {
-  const uint32_t enum_value = rel_types & (RelTypeHistogramEnumMax - 1);
+  const RelTypeHistogramEnum enum_value = static_cast<RelTypeHistogramEnum>(
+      rel_types & (RelTypeHistogramEnumMax - 1));
   UMA_HISTOGRAM_ENUMERATION("Prerender.RelTypesLinkAdded", enum_value,
                             RelTypeHistogramEnumMax);
 }
 
 void RecordLinkManagerStarting(const uint32_t rel_types) {
-  const uint32_t enum_value = rel_types & (RelTypeHistogramEnumMax - 1);
+  const RelTypeHistogramEnum enum_value = static_cast<RelTypeHistogramEnum>(
+      rel_types & (RelTypeHistogramEnumMax - 1));
   UMA_HISTOGRAM_ENUMERATION("Prerender.RelTypesLinkStarted", enum_value,
                             RelTypeHistogramEnumMax);
 }
 
 void Send(int child_id, IPC::Message* raw_message) {
   using content::RenderProcessHost;
   std::unique_ptr<IPC::Message> own_message(raw_message);
 
   RenderProcessHost* render_process_host = RenderProcessHost::FromID(child_id);
   if (!render_process_host)
@@ skipping 436 matching lines @@
   Send(prerender->launcher_child_id,
       new PrerenderMsg_OnPrerenderStop(prerender->prerender_id));
   RemovePrerender(prerender);
   StartPrerenders();
 }
 
 void PrerenderLinkManager::OnPrerenderNetworkBytesChanged(
     PrerenderHandle* prerender_handle) {}
 
 }  // namespace prerender