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

components/contextual_search/renderer/overlay_js_render_frame_observer.h

 // Copyright 2015 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_CONTEXTUAL_SEARCH_RENDERER_OVERLAY_JS_RENDER_FRAME_OBSERVER_H_
 #define COMPONENTS_CONTEXTUAL_SEARCH_RENDERER_OVERLAY_JS_RENDER_FRAME_OBSERVER_H_
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "components/contextual_search/common/overlay_page_notifier_service.mojom.h"
 #include "content/public/renderer/render_frame.h"
 #include "content/public/renderer/render_frame_observer.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "v8/include/v8.h"
 
 namespace contextual_search {
 
 // OverlayJsRenderFrame observer waits for a page to be loaded and then
 // tries to connect to a mojo service hosted in the browser process. The
 // service will tell this render process if the current page is presented
 // in an overlay panel.
 class OverlayJsRenderFrameObserver : public content::RenderFrameObserver {
  public:
   explicit OverlayJsRenderFrameObserver(content::RenderFrame* render_frame);
   ~OverlayJsRenderFrameObserver() override;
 
   // RenderFrameObserver implementation.
-  void DidStartProvisionalLoad() override;
+  void DidStartProvisionalLoad(blink::WebDataSource* data_source) override;
   void DidClearWindowObject() override;
   void DidFinishLoad() override;
 
   // Flag the current page as a contextual search overlay.
   void SetIsContextualSearchOverlay();
 
  private:
   // RenderFrameObserver implementation.
   void OnDestruct() override;
 
@@ skipping 11 matching lines @@
   bool is_contextual_search_overlay_;
 
   base::WeakPtrFactory<OverlayJsRenderFrameObserver> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OverlayJsRenderFrameObserver);
 };
 
 }  // namespace contextual_search
 
 #endif  // COMPONENTS_CONTEXTUAL_SEARCH_RENDERER_OVERLAY_JS_RENDER_FRAME_OBSERVER_H_