PlzNavigate: Invoke didStartProvisionalLoad() when the renderer initiates a navigation in startLoad(

components/test_runner/web_frame_test_proxy.h

Index: components/test_runner/web_frame_test_proxy.h
diff --git a/components/test_runner/web_frame_test_proxy.h b/components/test_runner/web_frame_test_proxy.h
index ac444304046335918db5624824178fd29d0a7339..841da45cc92a9b8e6f4c33994e8dec241362a186 100644
--- a/components/test_runner/web_frame_test_proxy.h
+++ b/components/test_runner/web_frame_test_proxy.h
@@ -96,9 +96,10 @@ class WebFrameTestProxy : public Base, public WebFrameTestProxyBase {
                             replaces_current_history_item);
   }
 
-  void didStartProvisionalLoad(blink::WebLocalFrame* frame) override {
-    test_client()->didStartProvisionalLoad(frame);
-    Base::didStartProvisionalLoad(frame);
+  void didStartProvisionalLoad(blink::WebLocalFrame* frame,
+                               blink::WebDataSource* data_source) override {
+    test_client()->didStartProvisionalLoad(frame, data_source);
+    Base::didStartProvisionalLoad(frame, data_source);
   }
 
   void didReceiveServerRedirectForProvisionalLoad(