Autoplay: use an autoplay policy setting in Blink.

third_party/WebKit/Source/core/html/media/AutoplayPolicy.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef AutoplayPolicy_h
 #define AutoplayPolicy_h
 
 #include "bindings/core/v8/Nullable.h"
+#include "core/CoreExport.h"
 #include "core/dom/ExceptionCode.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
 class AutoplayUmaHelper;
 class Document;
 class ElementVisibilityObserver;
 class HTMLMediaElement;
 
 // AutoplayPolicy is the class for handles autoplay logics.
 class AutoplayPolicy final : public GarbageCollected<AutoplayPolicy> {
  public:
+  // Different autoplay policy types.
+  enum class Type {
+    kNoUserGestureRequired = 0,
+    kUserGestureRequired,
+    kUserGestureRequiredForCrossOrigin,
+  };
+
+  CORE_EXPORT static Type GetAutoplayPolicyForDocument(const Document&);
+
   explicit AutoplayPolicy(HTMLMediaElement*);
 
   void VideoWillBeDrawnToCanvas() const;
 
   // Called when the media element is moved to a new document.
   void DidMoveToNewDocument(Document& old_document);
 
   // Stop autoplaying the video element whenever its visible.
   // TODO(mlamouri): hide these methods from HTMLMediaElement.
   void StopAutoplayMutedWhenVisible();
@@ skipping 72 matching lines @@
   Member<ElementVisibilityObserver> autoplay_visibility_observer_;
 
   Member<AutoplayUmaHelper> autoplay_uma_helper_;
 
   DISALLOW_COPY_AND_ASSIGN(AutoplayPolicy);
 };
 
 }  // namespace blink
 
 #endif  // AutoplayPolicy_h