[Picture-in-Picture] Do not pause PiP video when removed from document

This CL makes sure video do not pause when playing in Picture-in-Picture
and subsequently removed from the Document.

Spec: https://github.com/w3c/picture-in-picture/issues/99

Change-Id: Ifefd961803cc47c64d394aa52454313cbcef603a
Bug: 1167643
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2627311
Commit-Queue: François Beaufort <beaufort.francois@gmail.com>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Cr-Commit-Position: refs/heads/master@{#845100}

third_party/blink/renderer/core/html/media/html_media_element.cc

@@ -71,6 +71,7 @@
 #include "third_party/blink/renderer/core/frame/local_frame.h"
 #include "third_party/blink/renderer/core/frame/local_frame_client.h"
 #include "third_party/blink/renderer/core/frame/local_frame_view.h"
+#include "third_party/blink/renderer/core/frame/picture_in_picture_controller.h"
 #include "third_party/blink/renderer/core/frame/settings.h"
 #include "third_party/blink/renderer/core/fullscreen/fullscreen.h"
 #include "third_party/blink/renderer/core/html/html_source_element.h"
@@ -4290,7 +4291,10 @@ void HTMLMediaElement::OnRemovedFromDocumentTimerFired(TimerBase*) {
   if (InActiveDocument())
     return;
 
-  PauseInternal();
+  // Video should not pause when playing in Picture-in-Picture and subsequently
+  // removed from the Document.
+  if (!PictureInPictureController::IsElementInPictureInPicture(this))
+    PauseInternal();
 }
 
 void HTMLMediaElement::AudioSourceProviderImpl::Wrap(

third_party/blink/web_tests/android/ChromiumWPTExpectations

@@ -3541,6 +3541,7 @@ crbug.com/1050754 external/wpt/picture-in-picture/picture-in-picture-element.htm
 crbug.com/1050754 external/wpt/picture-in-picture/picture-in-picture-window.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/request-picture-in-picture-twice.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/request-picture-in-picture.html [ Failure ]
+crbug.com/1050754 external/wpt/picture-in-picture/removed-from-document.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/shadow-dom.html [ Failure ]
 crbug.com/1050754 external/wpt/pointerevents/compat/pointerevent_compat-mouse-events-when-removing-nodes.html [ Failure Pass ]
 crbug.com/1050754 external/wpt/pointerevents/compat/pointerevent_mouse-on-object.html [ Failure ]

third_party/blink/web_tests/android/WeblayerWPTExpectations

@@ -3627,6 +3627,7 @@ crbug.com/1050754 external/wpt/picture-in-picture/picture-in-picture-element.htm
 crbug.com/1050754 external/wpt/picture-in-picture/picture-in-picture-window.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/request-picture-in-picture-twice.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/request-picture-in-picture.html [ Failure ]
+crbug.com/1050754 external/wpt/picture-in-picture/removed-from-document.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/shadow-dom.html [ Failure ]
 crbug.com/1050754 external/wpt/pointerevents/compat/pointerevent_compat-mouse-events-when-removing-nodes.html [ Failure Pass ]
 crbug.com/1050754 external/wpt/pointerevents/compat/pointerevent_mouse-on-object.html [ Failure ]

third_party/blink/web_tests/android/WebviewWPTExpectations

@@ -3909,6 +3909,7 @@ crbug.com/1050754 external/wpt/picture-in-picture/picture-in-picture-element.htm
 crbug.com/1050754 external/wpt/picture-in-picture/picture-in-picture-window.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/request-picture-in-picture-twice.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/request-picture-in-picture.html [ Failure ]
+crbug.com/1050754 external/wpt/picture-in-picture/removed-from-document.html [ Failure ]
 crbug.com/1050754 external/wpt/picture-in-picture/shadow-dom.html [ Failure ]
 crbug.com/1050754 external/wpt/pointerevents/compat/pointerevent_compat-mouse-events-when-removing-nodes.html [ Failure Pass ]
 crbug.com/1050754 external/wpt/pointerevents/compat/pointerevent_mouse-on-object.html [ Failure Pass ]

third_party/blink/web_tests/external/wpt/picture-in-picture/removed-from-document.html

+<!DOCTYPE html>
+<title>Test Picture-in-Picture when removed from document</title>
+<script src="/common/media.js"></script>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+<script src="resources/picture-in-picture-helpers.js"></script>
+<body></body>
+<script>
+promise_test(async t => {
+  const video = await loadVideo();
+  document.body.appendChild(video);
+  video.muted = true;
+  await video.play();
+  await requestPictureInPictureWithTrustedClick(video);
+
+  assert_false(video.paused);
+  document.body.offsetLeft;
+  document.body.removeChild(video);
+  await new Promise(resolve => step_timeout(resolve, 1000));
+  assert_false(video.paused);
+}, 'Picture-in-Picture video does not pause when removed from document');
+</script>