(blink) Propagate scrolling/marginwidth/marginheight property values to child frame.

Source/web/RemoteBridgeFrameOwner.h

 // Copyright 2015 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 RemoteBridgeFrameOwner_h
 #define RemoteBridgeFrameOwner_h
 
 #include "core/frame/FrameOwner.h"
+#include "platform/scroll/ScrollTypes.h"
 #include "web/WebLocalFrameImpl.h"
 
 namespace blink {
 
 // Helper class to bridge communication for a frame with a remote parent.
 // Currently, it serves two purposes:
 // 1. Allows the local frame's loader to retrieve sandbox flags associated with
 //    its owner element in another process.
 // 2. Trigger a load event on its owner element once it finishes a load.
 class RemoteBridgeFrameOwner final : public NoBaseWillBeGarbageCollectedFinalized<RemoteBridgeFrameOwner>, public FrameOwner {
@@ skipping 24 matching lines @@
         m_frame = frame;
     }
 
     void dispatchLoad() override;
 
     void renderFallbackContent() override
     {
         // TODO(dcheng): Implement.
     }
 
+    void setScrollingMode(ScrollbarMode mode) { m_scrolling = mode; }
+    void setMarginWidth(int marginWidth) { m_marginWidth = marginWidth; }
+    void setMarginHeight(int marginHeight) { m_marginHeight = marginHeight; }
+
+    ScrollbarMode scrollingMode() const override { return m_scrolling; }
+    int marginWidth() const override { return m_marginWidth; }
+    int marginHeight() const override { return m_marginHeight; }
+
     DECLARE_VIRTUAL_TRACE();
 
 private:
     RemoteBridgeFrameOwner(PassRefPtrWillBeRawPtr<WebLocalFrameImpl>, SandboxFlags);
 
     RefPtrWillBeMember<WebLocalFrameImpl> m_frame;
     SandboxFlags m_sandboxFlags;
+    ScrollbarMode m_scrolling;
+    int m_marginWidth;
+    int m_marginHeight;
 };
 
 DEFINE_TYPE_CASTS(RemoteBridgeFrameOwner, FrameOwner, owner, !owner->isLocal(), !owner.isLocal());
 
 } // namespace blink
 
 #endif // RemoteBridgeFrameOwner_h