Make options zoom isolated, match embedder zoom on navigation.

components/ui/zoom/zoom_controller.cc

 // Copyright (c) 2012 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.
 
 #include "components/ui/zoom/zoom_controller.h"
 
 #include "components/ui/zoom/zoom_event_manager.h"
 #include "components/ui/zoom/zoom_observer.h"
 #include "content/public/browser/host_zoom_map.h"
 #include "content/public/browser/navigation_details.h"
@@ skipping 117 matching lines @@
                                              false /* can_show_bubble */));
   int render_process_id = web_contents()->GetRenderProcessHost()->GetID();
   int render_view_id = web_contents()->GetRenderViewHost()->GetRoutingID();
   if (zoom_mode_ == ZOOM_MODE_ISOLATED ||
       zoom_map->UsesTemporaryZoomLevel(render_process_id, render_view_id)) {
     zoom_map->SetTemporaryZoomLevel(render_process_id, render_view_id,
                                     zoom_level);
   } else {
     if (!entry) {
       last_client_ = NULL;
+      // If we exit without triggering an update, we should clear event_data_,
+      // else we may later trigger a DCHECK(event_data_).
+      event_data_.reset();
       return false;
     }
     std::string host =
         net::GetHostOrSpecFromURL(content::HostZoomMap::GetURLFromEntry(entry));
     zoom_map->SetZoomLevelForHost(host, zoom_level);
   }
 
   DCHECK(!event_data_);
   last_client_ = NULL;
   return true;
@@ skipping 198 matching lines @@
   int render_view_id = web_contents()->GetRenderViewHost()->GetRoutingID();
   host_zoom_map_->SetPageScaleFactorIsOneForView(
       render_process_id, render_view_id, is_one);
 }
 
 bool ZoomController::PageScaleFactorIsOne() const {
   return content::HostZoomMap::PageScaleFactorIsOne(web_contents());
 }
 
 }  // namespace ui_zoom