[RemotePlayback] Keep track of source compatibility and reject prompt() correspondingly

third_party/WebKit/Source/core/paint/VideoPainterTest.cpp

Index: third_party/WebKit/Source/core/paint/VideoPainterTest.cpp
diff --git a/third_party/WebKit/Source/core/paint/VideoPainterTest.cpp b/third_party/WebKit/Source/core/paint/VideoPainterTest.cpp
index b481b99c71659418db0ce006f339c4fbf65f2219..5daf72093c8af256f194583d86cfa808bf889c70 100644
--- a/third_party/WebKit/Source/core/paint/VideoPainterTest.cpp
+++ b/third_party/WebKit/Source/core/paint/VideoPainterTest.cpp
@@ -87,6 +87,12 @@ class StubFrameLoaderClient : public EmptyFrameLoaderClient {
       WebMediaPlayerClient* client) override {
     return wrapUnique(new StubWebMediaPlayer(client));
   }
+
+  WebRemotePlaybackClient* createWebRemotePlaybackClient(
+      HTMLMediaElement&,
+      ScriptState*) override {
+    return nullptr;
+  }
 };
 
 class VideoPainterTestForSPv2 : public ::testing::Test {