Plumb whether or not a frame is in shadow DOM to the embedder.

public/web/WebRemoteFrame.h

Index: public/web/WebRemoteFrame.h
diff --git a/public/web/WebRemoteFrame.h b/public/web/WebRemoteFrame.h
index 774783c015a0b44b68c73cc89decbfdf128d56f8..999b420391caa0e89d234acd72fc79c9857e496a 100644
--- a/public/web/WebRemoteFrame.h
+++ b/public/web/WebRemoteFrame.h
@@ -10,15 +10,24 @@
 
 namespace blink {
 
+enum class WebTreeScopeType;
 class WebFrameClient;
 class WebRemoteFrameClient;
 
 class WebRemoteFrame : public WebFrame {
 public:
     BLINK_EXPORT static WebRemoteFrame* create(WebRemoteFrameClient*);
-
+    BLINK_EXPORT static WebRemoteFrame* create(WebTreeScopeType, WebRemoteFrameClient*);
+
+    // Functions for the embedder replicate the frame tree between processes.
+    // TODO(dcheng): The embedder currently does not replicate local frames in
+    // insertion order, so the local child version takes a previous sibling to
+    // ensure that it is inserted into the correct location in the list of
+    // children.
+    virtual WebLocalFrame* createLocalChild(WebTreeScopeType, const WebString& name, WebSandboxFlags, WebFrameClient*, WebFrame* previousSibling) = 0;
     virtual WebLocalFrame* createLocalChild(const WebString& name, WebSandboxFlags, WebFrameClient*, WebFrame* previousSibling) = 0;
 
+    virtual WebRemoteFrame* createRemoteChild(WebTreeScopeType, const WebString& name, WebSandboxFlags, WebRemoteFrameClient*) = 0;
     virtual WebRemoteFrame* createRemoteChild(const WebString& name, WebSandboxFlags, WebRemoteFrameClient*) = 0;
 
     // Transfer initial drawing parameters from a local frame.
@@ -37,6 +46,9 @@ public:
 
     virtual void didStartLoading() = 0;
     virtual void didStopLoading() = 0;
+
+protected:
+    explicit WebRemoteFrame(WebTreeScopeType scope) : WebFrame(scope) { }
 };
 
 } // namespace blink