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

public/web/WebLocalFrame.h

 // Copyright 2014 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 WebLocalFrame_h
 #define WebLocalFrame_h
 
 #include "WebFrame.h"
 
 namespace blink {
 
 enum class WebAppBannerPromptReply;
 enum class WebSandboxFlags;
+enum class WebTreeScopeType;
 class WebAutofillClient;
 class WebContentSettingsClient;
 class WebDevToolsAgent;
 class WebDevToolsAgentClient;
 class WebFrameClient;
 class WebNode;
 class WebScriptExecutionCallback;
 class WebSuspendableTask;
 struct WebPrintPresetOptions;
 
 // Interface for interacting with in process frames. This contains methods that
 // require interacting with a frame's document.
 // FIXME: Move lots of methods from WebFrame in here.
 class WebLocalFrame : public WebFrame {
 public:
     // Creates a WebFrame. Delete this WebFrame by calling WebFrame::close().
     // It is valid to pass a null client pointer.
+    BLINK_EXPORT static WebLocalFrame* create(WebTreeScopeType, WebFrameClient*);
+    // TODO(dcheng): Remove this deprecated overload.
     BLINK_EXPORT static WebLocalFrame* create(WebFrameClient*);
 
     // Returns the WebFrame associated with the current V8 context. This
     // function can return 0 if the context is associated with a Document that
     // is not currently being displayed in a Frame.
     BLINK_EXPORT static WebLocalFrame* frameForCurrentContext();
 
     // Returns the frame corresponding to the given context. This can return 0
     // if the context is detached from the frame, or if the context doesn't
     // correspond to a frame (e.g., workers).
@@ skipping 94 matching lines @@
     virtual void willShowInstallBannerPrompt(int requestId, const WebVector<WebString>& platforms, WebAppBannerPromptReply*) = 0;
 
     // Old version of the above function missing |requestId|.
     // TODO(benwells): remove this once the above is rolled into chrome.
     virtual void willShowInstallBannerPrompt(const WebVector<WebString>& platforms, WebAppBannerPromptReply*) = 0;
 
     // Image reload -----------------------------------------------------------
 
     // If the provided node is an image, reload the image bypassing the cache.
     virtual void reloadImage(const WebNode&) = 0;
+
+protected:
+    explicit WebLocalFrame(WebTreeScopeType scope) : WebFrame(scope) { }
 };
 
 } // namespace blink
 
 #endif // WebLocalFrame_h