PlzNavigate: Get StreamPrivate API to work.

content/public/browser/web_contents.h

Index: content/public/browser/web_contents.h
diff --git a/content/public/browser/web_contents.h b/content/public/browser/web_contents.h
index 37b3bf2b5d759f6de4423e4e09434e85d4206541..1eb4d7c0c60b656b6b1918b8f7ae61be99089e69 100644
--- a/content/public/browser/web_contents.h
+++ b/content/public/browser/web_contents.h
@@ -186,6 +186,10 @@ class WebContents : public PageNavigator,
 
   CONTENT_EXPORT static WebContents* FromRenderFrameHost(RenderFrameHost* rfh);
 
+  // Returns the WebContents associated with the |frame_tree_node_id|.
+  CONTENT_EXPORT static WebContents* FromFrameTreeNodeId(
+      int frame_tree_node_id);

[nasko, 2016/09/21 21:32:18]

I know we might need to do this at some point, but I'm not convinced that this
CL requires it quite yet.

[ananta, 2016/09/21 21:59:12]

Please refer to the comments from jam in an earlier patchset.

+
   ~WebContents() override {}
 
   // Intrinsic tab state -------------------------------------------------------