[Media Router] Show user email in header if cloud sink is present.

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 7be4f3302903c383a71bda1e697580f9481cdaaa..7c2c69274568b2ea49514e7f4387188aa48ebcd9 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
@@ -192,6 +192,15 @@ std::string GetLearnMoreUrl(const base::DictionaryValue* args) {
   return help_url;
 }
 
+bool SinksWithDomainInList(const std::vector<MediaSinkWithCastModes>& sinks) {
+  for (const MediaSinkWithCastModes& sink_with_cast_modes : sinks) {
+    const MediaSink& sink = sink_with_cast_modes.sink;
+    if (!sink.domain().empty())
+      return true;
+  }
+  return false;
+}
+
 }  // namespace
 
 MediaRouterWebUIMessageHandler::MediaRouterWebUIMessageHandler(
@@ -376,14 +385,20 @@ void MediaRouterWebUIMessageHandler::OnRequestInitialData(
   // enabled. If the user enables sync after acknowledging the first run flow,
   // this is treated as the user opting into Google services, including cloud
   // services, if the browser is a Chrome branded build.
+    SigninManagerBase* signin_manager =
+    SigninManagerFactory::GetForProfile(profile);
   if (!profile->GetPrefs()->GetBoolean(
           prefs::kMediaRouterCloudServicesPrefSet) &&
       profile->IsSyncAllowed()) {
-    SigninManagerBase* signin_manager =
-        SigninManagerFactory::GetForProfile(profile);
     show_cloud_pref = signin_manager && signin_manager->IsAuthenticated() &&
         ProfileSyncServiceFactory::GetForProfile(profile)->IsSyncActive();
   }
+  initial_data.SetString("userEmail",

[apacible, 2016/02/11 17:09:14]

What would the behavior be like for scenarios where the user logs in/out while
the dialog is open?

For example:
1. User logs in. User opens dialog. User logs out.
2. User is not logged in. User opens dialog. User logs in.
3. (similar to 2) User logs in. User opens dialog. User logs out. User logs into
a second email.

[amp, 2016/02/11 21:21:24]

If the dialogue is still open and still shows sinks with domains, then it should
still show the emails associated with those sinks.  If the cloud mrp updates the
list and clears them out (perhaps we should add a bug to track doing that) then
the email should be removed as there are no more sinks associated with it.
Probably nothing as I don't think the cloud mrp will run discover until the next
time the dialog is opened.
That one gets tricky, but the cloud mrp should track when login changes and
clear it's list (removing the email).  If the user logs back in I'm still
thinking nothing will show up (same as #2) until the next run of the dialog,
which should give us a chance to update the email address to the new one (I
think).

[apacible, 2016/02/12 21:26:15]

Would the cloud mrp run discover when we do a sink query in general? I'm not
familiar with the expected behavior here.

I know MR can/will send updated sink lists while the dialog is open. I'd also
expect that with the cloud sinks. If we don't do that, is that for performance
reasons? 

[amp, 2016/02/13 02:11:05]

The CloudMRP will get the same queries, but it ignores them unless they are for
tab or desktop casting.  It also may not be responding to all the apis for
observing things. 

The cloud sinks do generally show up after the UI has been open for a few
seconds (the first time, subsequent times they are usually there from the
beginning), so it is dynamic in that sense.   I'm not sure I entirely understand
how it all works together either though.

I'll try to verify the behavior here with logging in and out etc and see what is
actually going to happen.

[apacible, 2016/02/13 08:13:02]

Acknowledged.

+      signin_manager->GetAuthenticatedAccountInfo().email);
+  initial_data.SetString("userDomain",
+      signin_manager->GetAuthenticatedAccountInfo().hosted_domain);
+  initial_data.SetBoolean("showEmail",
+      SinksWithDomainInList(media_router_ui_->sinks()));
 #endif  // defined(GOOGLE_CHROME_BUILD)
   initial_data.SetBoolean("showFirstRunFlowCloudPref", show_cloud_pref);