[Presentation API] 1-UA presentation support + presenter APIs.

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 0f9113561b6b3e947b78bc6421dd00819f02bfbe..80b6f63bb0a998be08b2ee0a77feb0a0c901cb6a 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -257,6 +257,7 @@
 
 #if defined(ENABLE_MEDIA_ROUTER)
 #include "chrome/browser/media/router/presentation_service_delegate_impl.h"
+#include "chrome/browser/media/router/receiver_presentation_service_delegate_impl.h"
 #endif
 
 using base::FileDescriptor;
@@ -2554,10 +2555,14 @@ content::PresentationServiceDelegate*
 ChromeContentBrowserClient::GetPresentationServiceDelegate(
       content::WebContents* web_contents) {
 #if defined(ENABLE_MEDIA_ROUTER)
-  if (switches::MediaRouterEnabled() &&
-      !web_contents->GetBrowserContext()->IsOffTheRecord()) {
-    return media_router::PresentationServiceDelegateImpl::
-        GetOrCreateForWebContents(web_contents);
+  if (switches::MediaRouterEnabled()) {
+    if (web_contents->GetBrowserContext()->IsOffTheRecord()) {

[mark a. foltz, 2015/10/01 06:25:28]

Does this assume that all incognito webcontents are presentations?  Maybe we
could add a webcontents->IsPresentation() method to make this clearer.

[imcheng, 2015/10/06 00:59:13]

Not all incognito WebContents are presentations. We only create
ReceiverPresentationServiceDelegateImpl for a WebContents in
offscreen_presentation.cc. So this function will still return nullptr for
non-receiver incognito WebContents .

+      return media_router::ReceiverPresentationServiceDelegateImpl::
+          FromWebContents(web_contents);
+    } else {
+      return media_router::PresentationServiceDelegateImpl::
+          GetOrCreateForWebContents(web_contents);
+    }
   }
 #endif
   return nullptr;