Cast Refactor: separate presentation setup/teardown from controllers.

This is a pre-step. The new CastService object will be managing the
lifetime of start_presentation_context_ and presentation_manager_, and
so it is necessary to detangle the setup/lifetime of these objects from
info stored in the controllers. This first step is to demonstrate that
this initial decoupling breaks no existing behavior. The next step will
be to create an initial CastService that will take over the lifetimes
of start_presentation_context_, presentation_manager_, and
query_result_manager_ exposing those objects plus some new events to
the controllers. The step after that will be to create a CastToSink
method to the Controller that, given a sink id, will create a route to
that sink id, and hide the presentation objects from the controllers.

BUG=b:201430609

Change-Id: I59251c0de05afc9016a01bf24cf0699c3a69a357
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3544126
Reviewed-by: Takumi Fujimoto <takumif@chromium.org>
Reviewed-by: George Benz <gbj@google.com>
Commit-Queue: Brian Malcolm <bmalcolm@chromium.org>
Cr-Commit-Position: refs/heads/main@{#985584}

chrome/browser/ui/media_router/media_router_ui.cc

@@ -126,8 +126,12 @@ MediaRouterUI::~MediaRouterUI() {
   // If |start_presentation_context_| still exists, then it means presentation
   // route request was never attempted.
   if (start_presentation_context_) {
+    std::vector<MediaSinkWithCastModes> sinks;
+    if (query_result_manager_.get()) {
+      sinks = query_result_manager_->GetSinksWithCastModes();
+    }
     bool presentation_sinks_available = std::any_of(
-        sinks_.begin(), sinks_.end(), [](const MediaSinkWithCastModes& sink) {
+        sinks.begin(), sinks.end(), [](const MediaSinkWithCastModes& sink) {
           return base::Contains(sink.cast_modes, MediaCastMode::PRESENTATION);
         });
     if (presentation_sinks_available) {
@@ -188,11 +192,6 @@ void MediaRouterUI::InitWithDefaultMediaSource() {
       presentation_manager_->HasDefaultPresentationRequest()) {
     OnDefaultPresentationChanged(
         &presentation_manager_->GetDefaultPresentationRequest());
-  } else {
-    // Register for MediaRoute updates without a media source.
-    routes_observer_ = std::make_unique<UIMediaRoutesObserver>(
-        GetMediaRouter(), base::BindRepeating(&MediaRouterUI::OnRoutesUpdated,
-                                              base::Unretained(this)));
   }
 }
 
@@ -424,6 +423,10 @@ void MediaRouterUI::InitCommon() {
       initiator_,
       base::BindRepeating(&MediaRouterUI::UpdateSinks, base::Unretained(this)));
 
+  routes_observer_ = std::make_unique<UIMediaRoutesObserver>(
+      GetMediaRouter(), base::BindRepeating(&MediaRouterUI::OnRoutesUpdated,
+                                            base::Unretained(this)));
+
   StartObservingIssues();
 }
 
@@ -460,22 +463,13 @@ void MediaRouterUI::OnDefaultPresentationChanged(
   query_result_manager_->SetSourcesForCastMode(
       MediaCastMode::PRESENTATION, sources,
       presentation_request_->frame_origin);
-  // Register for MediaRoute updates.
-  routes_observer_ = std::make_unique<UIMediaRoutesObserver>(
-      GetMediaRouter(), base::BindRepeating(&MediaRouterUI::OnRoutesUpdated,
-                                            base::Unretained(this)));
   UpdateModelHeader();
 }
 
 void MediaRouterUI::OnDefaultPresentationRemoved() {
   presentation_request_.reset();
   query_result_manager_->RemoveSourcesForCastMode(MediaCastMode::PRESENTATION);
 
-  // Register for MediaRoute updates.
-  routes_observer_ = std::make_unique<UIMediaRoutesObserver>(
-      GetMediaRouter(), base::BindRepeating(&MediaRouterUI::OnRoutesUpdated,
-                                            base::Unretained(this)));
-
   UpdateModelHeader();
 }
 

chrome/browser/ui/media_router/query_result_manager.cc

@@ -159,6 +159,22 @@ std::vector<MediaSource> QueryResultManager::GetSourcesForCastMode(
                                                   : cast_mode_it->second;
 }
 
+std::vector<MediaSinkWithCastModes> QueryResultManager::GetSinksWithCastModes()
+    const {
+  std::vector<MediaSinkWithCastModes> sinks;
+  for (const auto& sink_pair : sinks_with_sources_) {
+    MediaSinkWithCastModes sink_with_cast_modes(sink_pair.second.sink());
+    sink_with_cast_modes.cast_modes = sink_pair.second.GetCastModes();
+    sinks.push_back(sink_with_cast_modes);
+  }
+  for (const auto& sink : all_sinks_) {
+    if (!base::Contains(sinks_with_sources_, sink.id()))
+      sinks.push_back(MediaSinkWithCastModes(sink));
+  }
+
+  return sinks;
+}
+
 void QueryResultManager::RemoveOldSourcesForCastMode(
     MediaCastMode cast_mode,
     const std::vector<MediaSource>& new_sources) {
@@ -260,16 +276,7 @@ bool QueryResultManager::AreSourcesValidForCastMode(
 }
 
 void QueryResultManager::NotifyOnResultsUpdated() {
-  std::vector<MediaSinkWithCastModes> sinks;
-  for (const auto& sink_pair : sinks_with_sources_) {
-    MediaSinkWithCastModes sink_with_cast_modes(sink_pair.second.sink());
-    sink_with_cast_modes.cast_modes = sink_pair.second.GetCastModes();
-    sinks.push_back(sink_with_cast_modes);
-  }
-  for (const auto& sink : all_sinks_) {
-    if (!base::Contains(sinks_with_sources_, sink.id()))
-      sinks.push_back(MediaSinkWithCastModes(sink));
-  }
+  std::vector<MediaSinkWithCastModes> sinks = GetSinksWithCastModes();
   for (QueryResultManager::Observer& observer : observers_)
     observer.OnResultsUpdated(sinks);
 }

chrome/browser/ui/media_router/query_result_manager.h

@@ -114,6 +114,9 @@ class QueryResultManager {
   // vector if there is none.
   std::vector<MediaSource> GetSourcesForCastMode(MediaCastMode cast_mode) const;
 
+  // Returns all of the currently known sinks with the cast modes they support
+  std::vector<MediaSinkWithCastModes> GetSinksWithCastModes() const;
+
  private:
   class MediaSourceMediaSinksObserver;
   class AnyMediaSinksObserver;

chrome/browser/ui/webui/access_code_cast/access_code_cast_handler.cc

@@ -153,8 +153,15 @@ AccessCodeCastHandler::~AccessCodeCastHandler() {
   // If |start_presentation_context_| still exists, then it means presentation
   // route request was never attempted.
   if (start_presentation_context_) {
-    if (sink_id_ &&
-        base::Contains(supported_cast_modes_, MediaCastMode::PRESENTATION)) {
+    std::vector<MediaSinkWithCastModes> sinks;
+    if (query_result_manager_.get()) {
+      sinks = query_result_manager_->GetSinksWithCastModes();
+    }
+    bool presentation_sinks_available = std::any_of(
+        sinks.begin(), sinks.end(), [](const MediaSinkWithCastModes& sink) {
+          return base::Contains(sink.cast_modes, MediaCastMode::PRESENTATION);
+        });
+    if (presentation_sinks_available) {
       start_presentation_context_->InvokeErrorCallback(
           blink::mojom::PresentationError(blink::mojom::PresentationErrorType::
                                               PRESENTATION_REQUEST_CANCELLED,

chrome/browser/ui/webui/access_code_cast/access_code_cast_handler.h

@@ -150,8 +150,6 @@ class AccessCodeCastHandler : public access_code_cast::mojom::PageHandler,
 
   // The id of the media sink discovered from the access code;
   absl::optional<MediaSink::Id> sink_id_;
-  // Set of cast modes supported by the discovered sink;
-  media_router::CastModeSet supported_cast_modes_;
 
   // Monitors and reports sink availability.
   std::unique_ptr<QueryResultManager> query_result_manager_;