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

components/test_runner/web_frame_test_client.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_TEST_RUNNER_WEB_FRAME_TEST_CLIENT_H_
 #define COMPONENTS_TEST_RUNNER_WEB_FRAME_TEST_CLIENT_H_
 
 #include <map>
 #include <string>
 
@@ skipping 43 matching lines @@
   blink::WebUserMediaClient* userMediaClient() override;
   void didAddMessageToConsole(const blink::WebConsoleMessage& message,
                               const blink::WebString& source_name,
                               unsigned source_line,
                               const blink::WebString& stack_trace) override;
   void loadURLExternally(const blink::WebURLRequest& request,
                          blink::WebNavigationPolicy policy,
                          const blink::WebString& suggested_name,
                          bool replaces_current_history_item) override;
   void loadErrorPage(int reason) override;
-  void didStartProvisionalLoad(blink::WebLocalFrame* frame) override;
+  void didStartProvisionalLoad(blink::WebDataSource* data_source) override;
   void didReceiveServerRedirectForProvisionalLoad(
       blink::WebLocalFrame* frame) override;
   void didFailProvisionalLoad(blink::WebLocalFrame* frame,
                               const blink::WebURLError& error,
                               blink::WebHistoryCommitType commit_type) override;
   void didCommitProvisionalLoad(
       blink::WebLocalFrame* frame,
       const blink::WebHistoryItem& history_item,
       blink::WebHistoryCommitType history_type) override;
   void didReceiveTitle(blink::WebLocalFrame* frame,
@@ skipping 37 matching lines @@
   WebTestDelegate* delegate_;
   WebViewTestProxyBase* web_view_test_proxy_base_;
   WebFrameTestProxyBase* web_frame_test_proxy_base_;
 
   DISALLOW_COPY_AND_ASSIGN(WebFrameTestClient);
 };
 
 }  // namespace test_runner
 
 #endif  // COMPONENTS_TEST_RUNNER_WEB_FRAME_TEST_CLIENT_H_