Remove MediaControls methods needed for the Cast button

third_party/WebKit/Source/modules/media_controls/elements/MediaControlCastButtonElement.h

 // Copyright 2017 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.
 
 #ifndef MediaControlCastButtonElement_h
 #define MediaControlCastButtonElement_h
 
+#include "core/events/EventListener.h"
 #include "core/html/shadow/MediaControlElementTypes.h"
+#include "modules/remoteplayback/RemotePlayback.h"
 
 namespace blink {
 
 class Event;
 class MediaControlsImpl;
 
 class MediaControlCastButtonElement final : public MediaControlInputElement {
  public:
   MediaControlCastButtonElement(MediaControlsImpl&, bool is_overlay_button);
 
-  // This will show a cast button if it is not covered by another element.
-  // This MUST be called for cast button elements that are overlay elements.
-  void TryShowOverlay();
-
-  void SetIsPlayingRemotely(bool);
+  // If set to true, will show the button as long as the media element can be
+  // played remotely (and the button is not covered by another element, if it's
+  // an overlay). Will hide the button and stop watching for remote playback
+  // availability if set to false.
+  void SetIsWanted(bool) override;
 
   // MediaControlInputElement overrides.
   bool WillRespondToMouseClickEvents() override;
   WebLocalizedString::Name GetOverflowStringName() override;
   bool HasOverflowButton() override;
 
+  DECLARE_VIRTUAL_TRACE();
+
  private:
   // This is used for UMA histogram (Cast.Sender.Overlay). New values should
   // be appended only and must be added before |Count|.
   enum class CastOverlayMetrics {
     kCreated = 0,
     kShown,
     kClicked,
     kCount  // Keep last.
   };
 
+  // An event listener attached to the RemotePlayback object of the media
+  // element to handle state changes and update the button look.
+  class RemotePlaybackEventListener : public EventListener {
+   public:
+    explicit RemotePlaybackEventListener(MediaControlCastButtonElement*);
+    ~RemotePlaybackEventListener() = default;
+
+    void handleEvent(ExecutionContext*, Event*) override;
+    bool operator==(const EventListener& other) const override;
+
+    DECLARE_VIRTUAL_TRACE();
+
+   private:
+    Member<MediaControlCastButtonElement> cast_button_;
+  };
+
   void DefaultEventHandler(Event*) override;
   bool KeepEventInNode(Event*) override;
 
+  // Whether the media element is being played remotely at the moment.
+  bool IsPlayingRemotely() const;
+
+  // Updates the way the button is displayed (connected or not, overlay or not).
+  void UpdateDisplayType();
+
+  // Shows the button when all the conditions are met:
+  // - the MediaControlsImpl wants the button to be shown;
+  // - there're available remote playback devices;
+  // - the element is allowed to play remotely;
+  // - the button will NOT be obscured by another element (overlay).
+  void UpdateVisibility();
+
+  // Returns true if the button can be shown modulo the remote playback devices
+  // availability. Not const for implementation reasons.
+  bool ShouldShow();
+
   void RecordMetrics(CastOverlayMetrics);
 
   bool is_overlay_button_;
 
+  // Keeps track of whether the button needs to be shown from the
+  // MediaControlsImpl perspective.
+  bool is_wanted_by_controls_ = false;
+
+  // The index of the availability callback registered with |remote_playback_|
+  // or -1 if the callback is not registered.
+  int availability_callback_id_ = -1;
+
   // UMA related boolean. They are used to prevent counting something twice
   // for the same media element.
   bool click_use_counted_ = false;
   bool show_use_counted_ = false;
+
+  Member<RemotePlayback> remote_playback_;
+  Member<RemotePlaybackEventListener> remote_playback_event_listener_;
 };
 
 }  // namespace blink
 
 #endif  // MediaControlCastButtonElement_h