[Blink, RemotePlayback] Reject the prompt() with OperationError if there's a pending promise for th…

third_party/WebKit/Source/core/html/HTMLMediaElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp b/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
index d3c068511620f503cd454d8a48b6c819a81dba29..e7c6226cf13e243489847527eaeaae88e529f5e2 100644
--- a/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
@@ -2201,14 +2201,14 @@ void HTMLMediaElement::pauseInternal()
 
 void HTMLMediaElement::requestRemotePlayback()
 {
-    DCHECK(m_remoteRoutesAvailable);
-    webMediaPlayer()->requestRemotePlayback();
+    if (webMediaPlayer())
+        webMediaPlayer()->requestRemotePlayback();
 }
 
 void HTMLMediaElement::requestRemotePlaybackControl()
 {
-    DCHECK(m_remoteRoutesAvailable);
-    webMediaPlayer()->requestRemotePlaybackControl();
+    if (webMediaPlayer())
+        webMediaPlayer()->requestRemotePlaybackControl();
 }
 
 void HTMLMediaElement::closeMediaSource()