Media Session: use dictionary instead of an interface for MediaImage.

third_party/WebKit/Source/modules/mediasession/MediaImage.idl

Index: third_party/WebKit/Source/modules/mediasession/MediaImage.idl
diff --git a/third_party/WebKit/Source/modules/mediasession/MediaImage.idl b/third_party/WebKit/Source/modules/mediasession/MediaImage.idl
index fd33ba78bdc9692238d79bea4f41e1602b601f35..2a6fca6b0763006f71b68636cfd144a38b8f4fa9 100644
--- a/third_party/WebKit/Source/modules/mediasession/MediaImage.idl
+++ b/third_party/WebKit/Source/modules/mediasession/MediaImage.idl
@@ -2,14 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+// TODO: update link
 // https://wicg.github.io/mediasession/#the-mediaimage-interface
 
-[
-    ConstructorCallWith=ExecutionContext,
-    Constructor(MediaImageInit image),
-    RuntimeEnabled=MediaSession,
-] interface MediaImage {
-  readonly attribute USVString src;
-  readonly attribute DOMString sizes;
-  readonly attribute DOMString type;
+dictionary MediaImage {
+  USVString src;
+  DOMString sizes;
+  DOMString type;
 };