Media Remoting: Add interstitial elements to media element shadow dom.

third_party/WebKit/Source/core/css/mediaControls.css

Index: third_party/WebKit/Source/core/css/mediaControls.css
diff --git a/third_party/WebKit/Source/core/css/mediaControls.css b/third_party/WebKit/Source/core/css/mediaControls.css
index f13cb3dfcc2d344d7de2377fca0536f78c38af38..99c0652ac6d746cdc35349fe1b68d53994ae4c31 100644
--- a/third_party/WebKit/Source/core/css/mediaControls.css
+++ b/third_party/WebKit/Source/core/css/mediaControls.css
@@ -49,6 +49,19 @@ video::-webkit-media-controls {
     align-items: center;
 }
 
+audio::-webkit-media-remoting-interstitial,
+video::-webkit-media-remoting-interstitial {
+    width: inherit;
+    height: inherit;
+    position: relative;
+    direction: ltr;
+    display: flex;
+    flex-direction: column;
+    font-family: Segoe, "Helvetica Neue", Roboto, Arial, Helvetica, sans-serif;
+    justify-content: flex-end;
+    align-items: center;
+}
+
 audio::-webkit-media-controls-enclosure, video::-webkit-media-controls-enclosure {
     width: 100%;
     height: 32px;
@@ -145,6 +158,20 @@ video::-webkit-media-controls-overlay-play-button {
     padding: 0;
 }
 
+video::-webkit-media-remoting-disable-button {
+    -webkit-appearance: media-remoting-disable-button;
+    display: flex;
+    position: absolute;
+    margin: 0;
+    top: 28%;
+    left: 53%;
+    border-width: 0px;
+    background-color: transparent;
+    width: 48px;
+    height: 48px;
+    padding: 0;
+}
+
 video::-internal-media-controls-overlay-cast-button {
     -webkit-appearance: -internal-media-overlay-cast-off-button;
     display: flex;