Use FrameTreeNode ID as frameId in extension APIs

content/public/browser/resource_request_info.h

Index: content/public/browser/resource_request_info.h
diff --git a/content/public/browser/resource_request_info.h b/content/public/browser/resource_request_info.h
index 91deb56b75117a384665b1ad779670690a439be0..31c80f282c268f0d0dffa9cd235756c8cc287303 100644
--- a/content/public/browser/resource_request_info.h
+++ b/content/public/browser/resource_request_info.h
@@ -95,13 +95,9 @@ class ResourceRequestInfo {
   // True if GetRenderFrameID() represents a main frame in the RenderView.
   virtual bool IsMainFrame() const = 0;
 
-  // True if GetParentRenderFrameID() represents a main frame in the RenderView.
+  // True if the frame's parent represents a main frame in the RenderView.
   virtual bool ParentIsMainFrame() const = 0;
 
-  // Routing ID of parent frame of frame that sent this resource request.
-  // -1 if unknown / invalid.
-  virtual int GetParentRenderFrameID() const = 0;
-
   // Returns the associated resource type.
   virtual ResourceType GetResourceType() const = 0;