Use stricter type checking in UMA_HISTOGRAM_ENUMERATION

chrome/browser/android/metrics/launch_metrics.cc

 // Copyright (c) 2015 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/android/metrics/launch_metrics.h"
 
 #include "base/android/jni_string.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/time/time.h"
 #include "chrome/browser/android/shortcut_info.h"
@@ skipping 81 matching lines @@
       break;
     case ShortcutInfo::SOURCE_NOTIFICATION:
       rappor_metric_source = "Launch.HomeScreenSource.Notification";
       break;
     case ShortcutInfo::SOURCE_UNKNOWN:
     case ShortcutInfo::SOURCE_COUNT:
       rappor_metric_source = "Launch.HomeScreenSource.Unknown";
       break;
   }
 
-  UMA_HISTOGRAM_ENUMERATION("Launch.HomeScreenSource", histogram_source,
+  UMA_HISTOGRAM_ENUMERATION("Launch.HomeScreenSource",
+                            static_cast<ShortcutInfo::Source>(histogram_source),
                             ShortcutInfo::SOURCE_COUNT);
 
   rappor::SampleDomainAndRegistryFromGURL(g_browser_process->rappor_service(),
                                           rappor_metric_source, url);
 
-  int action = standalone ? HOME_SCREEN_LAUNCH_STANDALONE
-                          : HOME_SCREEN_LAUNCH_SHORTCUT;
+  HomeScreenLaunch action =
+      standalone ? HOME_SCREEN_LAUNCH_STANDALONE : HOME_SCREEN_LAUNCH_SHORTCUT;
   std::string rappor_metric_action = standalone ? "Launch.HomeScreen.Standalone"
                                                 : "Launch.HomeScreen.Shortcut";
 
   UMA_HISTOGRAM_ENUMERATION("Launch.HomeScreen", action,
                             HOME_SCREEN_LAUNCH_COUNT);
 
   rappor::SampleDomainAndRegistryFromGURL(g_browser_process->rappor_service(),
                                           rappor_metric_action, url);
 }
 
 static void RecordHomePageLaunchMetrics(
     JNIEnv* env,
     const JavaParamRef<jclass>& caller,
     jboolean show_home_button,
     jboolean homepage_is_ntp,
     const JavaParamRef<jstring>& jhomepage_url) {
   GURL homepage_url(base::android::ConvertJavaStringToUTF8(env, jhomepage_url));
   PrefMetricsService::RecordHomePageLaunchMetrics(
       show_home_button,
       homepage_is_ntp,
       homepage_url);
 }
 
 };  // namespace metrics