[Picture-in-Picture] Reset MediaPlayerId when user closes PiP window.

This makes sure the MediaPlayerId of the Picture-in-Picture video is
reset when user closes Picture-in-Picture window manually or when user
requests Picture-in-Picture several times.

Bug: 879592, 889011
Change-Id: I3ceea8de7fc5ee0e2c81268154daaa065b29b92b
Reviewed-on: https://chromium-review.googlesource.com/1236276Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Commit-Queue: François Beaufort <beaufort.francois@gmail.com>
Cr-Commit-Position: refs/heads/master@{#594441}

chrome/browser/picture_in_picture/picture_in_picture_window_controller_browsertest.cc

@@ -354,6 +354,9 @@ IN_PROC_BROWSER_TEST_F(PictureInPictureWindowControllerBrowserTest,
   // Stop video being played Picture-in-Picture and check if that's tracked.
   window_controller()->Close(true /* should_pause_video */);
   EXPECT_FALSE(active_web_contents->HasPictureInPictureVideo());
+
+  // Reload page should not crash.
+  ui_test_utils::NavigateToURL(browser(), test_page_url);
 }
 
 #if !defined(OS_ANDROID)
@@ -1335,12 +1338,6 @@ IN_PROC_BROWSER_TEST_F(PictureInPictureWindowControllerBrowserTest,
   EXPECT_TRUE(ExecuteScriptAndExtractBool(
       active_web_contents, "isInPictureInPicture();", &in_picture_in_picture));
   EXPECT_FALSE(in_picture_in_picture);
-
-  // TODO(edcourtney): When the renderer process is destroyed, it calls into
-  // MediaWebContentsObserver::ExitPictureInPictureInternal which Closes the
-  // current PIP. However, this may not be a WebContents sourced PIP, so this
-  // close can be spurious.
-  EXPECT_CALL(mock_controller(), Close(_));
 }
 
 IN_PROC_BROWSER_TEST_F(PictureInPictureWindowControllerBrowserTest,

content/browser/media/media_web_contents_observer.cc

@@ -123,6 +123,10 @@ MediaWebContentsObserver::GetPictureInPictureVideoMediaPlayerId() const {
   return pip_player_;
 }
 
+void MediaWebContentsObserver::ResetPictureInPictureVideoMediaPlayerId() {
+  pip_player_.reset();
+}
+
 bool MediaWebContentsObserver::OnMessageReceived(
     const IPC::Message& msg,
     RenderFrameHost* render_frame_host) {
@@ -380,7 +384,6 @@ void MediaWebContentsObserver::OnPictureInPictureSurfaceChanged(
     const gfx::Size& natural_size,
     bool show_play_pause_button) {
   DCHECK(surface_id.is_valid());
-  DCHECK(pip_player_);
 
   pip_player_ = MediaPlayerId(render_frame_host, delegate_id);
 
@@ -540,7 +543,7 @@ void MediaWebContentsObserver::ExitPictureInPictureInternal() {
 
   // Reset must happen after notifying the WebContents because it may interact
   // with it.
-  pip_player_.reset();
+  ResetPictureInPictureVideoMediaPlayerId();
 
   UpdateVideoLock();
 }

content/browser/media/media_web_contents_observer.h

@@ -74,6 +74,10 @@ class CONTENT_EXPORT MediaWebContentsObserver : public WebContentsObserver {
   const base::Optional<MediaPlayerId>& GetPictureInPictureVideoMediaPlayerId()
       const;
 
+  // Reset the MediaPlayerId of the picture in picture video when user closes
+  // Picture-in-Picture window manually.
+  void ResetPictureInPictureVideoMediaPlayerId();
+
   // WebContentsObserver implementation.
   void WebContentsDestroyed() override;
   void RenderFrameDeleted(RenderFrameHost* render_frame_host) override;

content/browser/picture_in_picture/picture_in_picture_window_controller_impl.cc

@@ -129,7 +129,7 @@ OverlayWindow* PictureInPictureWindowControllerImpl::GetWindowForTesting() {
 }
 
 void PictureInPictureWindowControllerImpl::UpdateLayerBounds() {
-  if (window_ && window_->IsVisible()) {
+  if (media_player_id_.has_value() && window_ && window_->IsVisible()) {
     media_web_contents_observer_->OnPictureInPictureWindowResize(
         window_->GetBounds().size());
   }
@@ -208,6 +208,7 @@ void PictureInPictureWindowControllerImpl::OnLeavingPictureInPicture(
         new MediaPlayerDelegateMsg_EndPictureInPictureMode(
             media_player_id_->render_frame_host->GetRoutingID(),
             media_player_id_->delegate_id));
+    media_web_contents_observer_->ResetPictureInPictureVideoMediaPlayerId();
   }
 }