Plumb initiator out of Blink.

content/renderer/render_frame_impl.cc

Index: content/renderer/render_frame_impl.cc
diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
index 679773f82aca83ced3397903a82c2e4dd7c899e6..11986c1fee0ecf96d69dd6ee6c8dab1e7f6130d2 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -3483,8 +3483,10 @@ void RenderFrameImpl::didCreateDataSource(blink::WebLocalFrame* frame,
           content_initiated));
 }
 
-void RenderFrameImpl::didStartProvisionalLoad(blink::WebDataSource* data_source,
-                                              blink::WebURLRequest& request) {
+void RenderFrameImpl::didStartProvisionalLoad(
+    blink::WebLocalFrame* initiator_frame,
+    blink::WebDataSource* data_source,
+    blink::WebURLRequest& request) {
   // In fast/loader/stop-provisional-loads.html, we abort the load before this
   // callback is invoked.
   if (!data_source)