[Media Router] Add P1 UMA metrics for Media Router.

chrome/browser/ui/webui/media_router/media_router_webui_message_handler.cc

Index: chrome/browser/ui/webui/media_router/media_router_webui_message_handler.cc
diff --git a/chrome/browser/ui/webui/media_router/media_router_webui_message_handler.cc b/chrome/browser/ui/webui/media_router/media_router_webui_message_handler.cc
index 3c44c1c3c9f8dad1fb056bdeeb6e5f2ccc14bbe7..9a7bcf31e82cd82e5921571038ffeece7231799b 100644
--- a/chrome/browser/ui/webui/media_router/media_router_webui_message_handler.cc
+++ b/chrome/browser/ui/webui/media_router/media_router_webui_message_handler.cc
@@ -7,6 +7,8 @@
 #include <string>
 
 #include "base/bind.h"
+#include "base/metrics/histogram.h"
+#include "base/metrics/histogram_base.h"

[Ilya Sherman, 2015/10/23 20:40:22]

Please replace these with a histogram_macros include.

[apacible, 2015/10/23 22:52:55]

Done.

 #include "base/strings/stringprintf.h"
 #include "chrome/browser/media/router/issue.h"
 #include "chrome/browser/ui/webui/media_router/media_router_ui.h"
@@ -27,6 +29,7 @@ const char kCreateRoute[] = "requestRoute";
 const char kActOnIssue[] = "actOnIssue";
 const char kCloseRoute[] = "closeRoute";
 const char kCloseDialog[] = "closeDialog";
+const char kReportSinkCount[] = "reportSinkCount";
 
 // JS function names.
 const char kSetInitialData[] = "media_router.ui.setInitialData";
@@ -202,10 +205,16 @@ void MediaRouterWebUIMessageHandler::OnCreateRouteResponseReceived(
         media_router_ui_->GetRouteProviderExtensionId()));
     web_ui()->CallJavascriptFunction(kOnCreateRouteResponseReceived,
                                      base::StringValue(sink_id), *route_value);
+
+    UMA_HISTOGRAM_BOOLEAN(
+        "MediaRouter.Ui.Action.StartLocalSessionSuccessful", true);
   } else {
     web_ui()->CallJavascriptFunction(kOnCreateRouteResponseReceived,
                                      base::StringValue(sink_id),
                                      *base::Value::CreateNullValue());
+
+    UMA_HISTOGRAM_BOOLEAN(
+        "MediaRouter.Ui.Action.StartLocalSessionSuccessful", false);

[Ilya Sherman, 2015/10/23 20:40:22]

Please record this as UMA_HISTOGRAM_BOOLEAN(..., route);, so that the macro is
only written once for this histogram.

[apacible, 2015/10/23 22:52:55]

Done.

[apacible, 2015/10/26 17:52:32]

Switched back because of these warnings:

e:\b\build\slave\win\build\src\chrome\browser\ui\webui\media_router\media_router_webui_message_handler.cc(214)
: error C2220: warning treated as error - no 'object' file generated
e:\b\build\slave\win\build\src\chrome\browser\ui\webui\media_router\media_router_webui_message_handler.cc(214)
: warning C4800: 'const media_router::MediaRoute *' : forcing value to bool
'true' or 'false' (performance warning)

   }
 }
 
@@ -246,6 +255,10 @@ void MediaRouterWebUIMessageHandler::RegisterMessages() {
       kCloseDialog,
       base::Bind(&MediaRouterWebUIMessageHandler::OnCloseDialog,
                  base::Unretained(this)));
+  web_ui()->RegisterMessageCallback(
+      kReportSinkCount,
+      base::Bind(&MediaRouterWebUIMessageHandler::OnReportSinkCount,
+                 base::Unretained(this)));
 }
 
 void MediaRouterWebUIMessageHandler::OnRequestInitialData(
@@ -373,6 +386,19 @@ void MediaRouterWebUIMessageHandler::OnCloseDialog(
   media_router_ui_->Close();
 }
 
+void MediaRouterWebUIMessageHandler::OnReportSinkCount(
+    const base::ListValue* args) {
+  DVLOG(1) << "OnReportSinkCount";
+  const base::DictionaryValue* args_dict = nullptr;
+  int sink_count = -1;
+  if (!args->GetDictionary(0, &args_dict) ||
+      !args_dict->GetInteger("sinkCount", &sink_count)) {
+    DVLOG(1) << "Unable to extract args.";
+    return;
+  }
+  UMA_HISTOGRAM_COUNTS_100("MediaRouter.Ui.Device.Count", sink_count);
+}
+
 bool MediaRouterWebUIMessageHandler::ActOnIssueType(
     const IssueAction::Type& action_type,
     const base::DictionaryValue* args) {