[Presentation API] (MR side) 1-UA: notify receiver page when receiver connection becomes available

chrome/browser/chrome_content_browser_client.cc

Index: chrome/browser/chrome_content_browser_client.cc
diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index 74f9a5c4606eccca2c5edbc14cbe57f37680ca00..13f22c29c3fc90fe2e350a4cc5a7f6405049a1dc 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -321,6 +321,7 @@
 #if defined(ENABLE_MEDIA_ROUTER)
 #include "chrome/browser/media/router/media_router_feature.h"
 #include "chrome/browser/media/router/presentation_service_delegate_impl.h"
+#include "chrome/browser/media/router/receiver_presentation_service_delegate_impl.h"
 #endif
 
 #if defined(ENABLE_WAYLAND_SERVER)
@@ -3003,6 +3004,13 @@ ChromeContentBrowserClient::GetPresentationServiceDelegate(
       content::WebContents* web_contents) {
 #if defined(ENABLE_MEDIA_ROUTER)
   if (media_router::MediaRouterEnabled(web_contents->GetBrowserContext())) {
+    // ReceiverPresentationServiceDelegateImpl are for WebContents created for

[mark a. foltz, 2016/10/04 00:32:20]

...exist only for WebContents

[zhaobin, 2016/10/04 02:42:59]

Done.

+    // offscreen presentations. The WebContents is from an incognito profile.

[mark a. foltz, 2016/10/04 00:32:20]

The WebContents must belong to an...

[zhaobin, 2016/10/04 02:42:59]

Done.

+    if (auto* impl = media_router::ReceiverPresentationServiceDelegateImpl::

[mark a. foltz, 2016/10/04 00:32:20]

Does this imply that the same WebContents cannot be a presentation receiver and
a presentation controller?

This is not something we plan on supporting in the near term, but might be worth
adding to the note above.

[zhaobin, 2016/10/04 02:42:59]

Done.

+            FromWebContents(web_contents)) {
+      DCHECK(web_contents->GetBrowserContext()->IsOffTheRecord());
+      return impl;
+    }
     return media_router::PresentationServiceDelegateImpl::
         GetOrCreateForWebContents(web_contents);
   }