[Picture in Picture] Close window when starting PiP in another tab.

Currently, we don't close the existing Picture-in-Picture window when
the a new tab (i.e. content::WebContents) initiates Picture-in-Picture
mode. This change tears down Picture-in-Picture mode for the current
video before opening a new one.

This change also pauses the video on user gesture to close. When the
Picture-in-Picture window is closed, the video in tab will not continue
playing, even if it was playing in the window.

BUG: 823172
Change-Id: I15e4ada29c6447fd15751503e1ad41868a89e71a
Reviewed-on: https://chromium-review.googlesource.com/1044752
Commit-Queue: apacible <apacible@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556692}

chrome/browser/ui/browser.cc

@@ -1413,6 +1413,12 @@ void Browser::UpdatePictureInPictureSurfaceId(const viz::SurfaceId& surface_id,
   if (!pip_window_controller_ ||
       pip_window_controller_->GetInitiatorWebContents() !=
           tab_strip_model_->GetActiveWebContents()) {
+    // If there was already a controller, close the existing window before
+    // creating the next one.
+    if (pip_window_controller_)
+      pip_window_controller_->Close();
+
+    // Update |pip_window_controller_| for the current content::WebContents.
     pip_window_controller_ =
         content::PictureInPictureWindowController::GetOrCreateForWebContents(
             tab_strip_model_->GetActiveWebContents());

content/browser/picture_in_picture/picture_in_picture_window_controller_impl.cc

@@ -47,17 +47,7 @@ PictureInPictureWindowControllerImpl::~PictureInPictureWindowControllerImpl() {
   if (initiator_->IsBeingDestroyed())
     return;
 
-  // |this| is torn down when there is a new Picture-in-Picture initiator, such
-  // as when a video in another tab requests to enter Picture-in-Picture. In
-  // cases like this, pause the current video so there is only one video
-  // playing at a time.
-  if (IsPlayerActive()) {
-    media_player_id_->first->Send(new MediaPlayerDelegateMsg_Pause(
-        media_player_id_->first->GetRoutingID(), media_player_id_->second));
-    media_player_id_->first->Send(
-        new MediaPlayerDelegateMsg_EndPictureInPictureMode(
-            media_player_id_->first->GetRoutingID(), media_player_id_->second));
-  }
+  OnLeavingPictureInPicture();
 }
 
 PictureInPictureWindowControllerImpl::PictureInPictureWindowControllerImpl(
@@ -88,11 +78,7 @@ void PictureInPictureWindowControllerImpl::Close() {
 
   surface_id_ = viz::SurfaceId();
 
-  if (IsPlayerActive()) {
-    media_player_id_->first->Send(
-        new MediaPlayerDelegateMsg_EndPictureInPictureMode(
-            media_player_id_->first->GetRoutingID(), media_player_id_->second));
-  }
+  OnLeavingPictureInPicture();
 }
 
 void PictureInPictureWindowControllerImpl::EmbedSurface(
@@ -144,4 +130,15 @@ bool PictureInPictureWindowControllerImpl::TogglePlayPause() {
   return true;
 }
 
+void PictureInPictureWindowControllerImpl::OnLeavingPictureInPicture() {
+  if (IsPlayerActive()) {
+    // Pause the current video so there is only one video playing at a time.
+    media_player_id_->first->Send(new MediaPlayerDelegateMsg_Pause(
+        media_player_id_->first->GetRoutingID(), media_player_id_->second));
+    media_player_id_->first->Send(
+        new MediaPlayerDelegateMsg_EndPictureInPictureMode(
+            media_player_id_->first->GetRoutingID(), media_player_id_->second));
+  }
+}
+
 }  // namespace content
\ No newline at end of file

content/browser/picture_in_picture/picture_in_picture_window_controller_impl.h

@@ -52,6 +52,9 @@ class PictureInPictureWindowControllerImpl
   CONTENT_EXPORT explicit PictureInPictureWindowControllerImpl(
       WebContents* initiator);
 
+  // Signal to the media player that |this| is leaving Picture-in-Picture mode.
+  void OnLeavingPictureInPicture();
+
   std::unique_ptr<OverlayWindow> window_;
   std::unique_ptr<OverlaySurfaceEmbedder> embedder_;
   WebContents* const initiator_;