clang/win: Enable -Wswitch.

chrome/browser/metrics/chrome_metrics_service_client.cc

 // Copyright 2014 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/metrics/chrome_metrics_service_client.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 373 matching lines @@
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(google_update_metrics_provider_));
 
   // Report exit funnels for canary and dev only.
   bool report_exit_funnels = false;
   switch (chrome::GetChannel()) {
     case version_info::Channel::CANARY:
     case version_info::Channel::DEV:
       report_exit_funnels = true;
       break;
+    case version_info::Channel::UNKNOWN:
+    case version_info::Channel::BETA:
+    case version_info::Channel::STABLE:
+      // report_exit_funnels was initialized to the right value above.
+      DCHECK(!report_exit_funnels);
+      break;
   }
 
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(
           new browser_watcher::WatcherMetricsProviderWin(
               chrome::kBrowserExitCodesRegistryPath, report_exit_funnels)));
 #endif  // defined(OS_WIN)
 
 #if defined(ENABLE_PLUGINS)
   plugin_metrics_provider_ =
@@ skipping 208 matching lines @@
     case content::NOTIFICATION_LOAD_START:
     case content::NOTIFICATION_RENDERER_PROCESS_CLOSED:
     case content::NOTIFICATION_RENDER_WIDGET_HOST_HANG:
       metrics_service_->OnApplicationNotIdle();
       break;
 
     default:
       NOTREACHED();
   }
 }