Add an ability to call WebKit's WebFrame::loadData via NavigationController.

content/public/browser/navigation_controller.h

Index: content/public/browser/navigation_controller.h
diff --git a/content/public/browser/navigation_controller.h b/content/public/browser/navigation_controller.h
index 28d20d30b73a1ba48d4efeda07103c7f585fb631..c8955d0d72b1fb501561e3627d3dd1ec0fd5da70 100644
--- a/content/public/browser/navigation_controller.h
+++ b/content/public/browser/navigation_controller.h
@@ -177,6 +177,15 @@ class NavigationController {
                                             const std::string& extra_headers,
                                             bool is_overriding_user_agent) = 0;
 
+  // Loads a 'data:' scheme URL with specified base URL and a history entry URL.
+  // This is only safe to be used for browser-initiated data: URL navigations,
+  // since it shows arbitrary content as if it comes from |history_url|.
+  virtual void LoadDataWithBaseURL(const GURL& data_url,
+                                   const Referrer& referrer,
+                                   const GURL& base_url,
+                                   const GURL& history_url,
+                                   bool is_overriding_user_agent) = 0;
+
   // Behaves like LoadURL() and LoadURLFromRenderer() but marks the new
   // navigation as being transferred from one RVH to another. In this case the
   // browser can recycle the old request once the new renderer wants to