[Media Router] Force DEFAULT cast mode when starting presentations from content.

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

 // Copyright 2015 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/ui/webui/media_router/media_router_ui.h"
 
 #include <algorithm>
 #include <string>
 #include <unordered_map>
 #include <utility>
@@ skipping 252 matching lines @@
     std::unique_ptr<CreatePresentationConnectionRequest>
         create_session_request) {
   DCHECK(initiator);
   DCHECK(delegate);
   DCHECK(create_session_request);
   DCHECK(!create_session_request_);
   DCHECK(!query_result_manager_);
 
   create_session_request_ = std::move(create_session_request);
   presentation_service_delegate_ = delegate->GetWeakPtr();
+
   InitCommon(initiator);
-  OnDefaultPresentationChanged(create_session_request_->presentation_request());
+  OnDefaultPresentationChanged(
+      create_session_request_->presentation_request());
 }
 
 void MediaRouterUI::InitCommon(content::WebContents* initiator) {
   DCHECK(initiator);
   DCHECK(router_);
 
   TRACE_EVENT_NESTABLE_ASYNC_INSTANT1("media_router", "UI", initiator,
                                       "MediaRouterUI::InitCommon", this);
 
+  // Presentation requests from content must show the origin requesting
+  // presentation: crbug.com/704964
+  if (create_session_request_)
+    forced_cast_mode_ = MediaCastMode::DEFAULT;
+
   router_->OnUserGesture();
 
   // Create |collator_| before |query_result_manager_| so that |collator_| is
   // already set up when we get a callback from |query_result_manager_|.
   UErrorCode error = U_ZERO_ERROR;
   const std::string& locale = g_browser_process->GetApplicationLocale();
   collator_.reset(
       icu::Collator::createInstance(icu::Locale(locale.c_str()), error));
   if (U_FAILURE(error)) {
     DLOG(ERROR) << "Failed to create collator for locale " << locale;
@@ skipping 56 matching lines @@
   routes_observer_.reset(new UIMediaRoutesObserver(
       router_, source_for_route_observer.id(),
       base::Bind(&MediaRouterUI::OnRoutesUpdated, base::Unretained(this))));
 
   UpdateCastModes();
 }
 
 void MediaRouterUI::OnDefaultPresentationRemoved() {
   presentation_request_.reset();
   query_result_manager_->RemoveSourcesForCastMode(MediaCastMode::DEFAULT);
+
+  // This should not be set if the dialog was initiated with a default
+  // presentation request from the top level frame.  However, clear it just to
+  // be safe.
+  forced_cast_mode_ = base::nullopt;
+
   // Register for MediaRoute updates without a media source.
   routes_observer_.reset(new UIMediaRoutesObserver(
       router_, MediaSource::Id(),
       base::Bind(&MediaRouterUI::OnRoutesUpdated, base::Unretained(this))));
   UpdateCastModes();
 }
 
 void MediaRouterUI::UpdateCastModes() {
   // Gets updated cast modes from |query_result_manager_| and forwards it to UI.
   cast_modes_ = query_result_manager_->GetSupportedCastModes();
   if (ui_initialized_) {
-    handler_->UpdateCastModes(cast_modes_, GetPresentationRequestSourceName());
+    handler_->UpdateCastModes(cast_modes_, GetPresentationRequestSourceName(),
+                              forced_cast_mode());
   }
 }
 
 void MediaRouterUI::UpdateRoutesToCastModesMapping() {
   std::unordered_map<MediaSource::Id, MediaCastMode> available_source_map;
   for (const auto& cast_mode : cast_modes_) {
     for (const auto& source :
          query_result_manager_->GetSourcesForCastMode(cast_mode)) {
       available_source_map.insert(std::make_pair(source.id(), cast_mode));
     }
@@ skipping 433 matching lines @@
 }
 
 std::string MediaRouterUI::GetSerializedInitiatorOrigin() const {
   url::Origin origin = initiator_
                            ? url::Origin(initiator_->GetLastCommittedURL())
                            : url::Origin();
   return origin.Serialize();
 }
 
 }  // namespace media_router