Moving extension code out of "components/" to avoid layering violations.

components/renderer_context_menu/context_menu_content_type.h

Index: components/renderer_context_menu/context_menu_content_type.h
diff --git a/components/renderer_context_menu/context_menu_content_type.h b/components/renderer_context_menu/context_menu_content_type.h
index c1e6a74f375c9ccdd7a5a7c914c29607a0e905b9..e7143f470284e73216dabf8a0ea51db3d9aba8ab 100644
--- a/components/renderer_context_menu/context_menu_content_type.h
+++ b/components/renderer_context_menu/context_menu_content_type.h
@@ -13,10 +13,6 @@ namespace content {
 class WebContents;
 }
 
-namespace extensions {
-class Extension;
-}
-
 // ContextMenuContentType is a helper to decide which category/group of items
 // are relevant for a given WebContents and a context.
 //
@@ -68,9 +64,8 @@ class ContextMenuContentType {
  protected:
   const content::ContextMenuParams& params() const { return params_; }
 
-  const extensions::Extension* GetExtension() const;
-
-  const content::WebContents* source_web_contents() const {
+  // TODO(lazyboy): Return const content::WebContents*.
+  content::WebContents* source_web_contents() const {
     return source_web_contents_;
   }