Create GoogleURLTrackerClient interface and //chrome implementation

chrome/browser/google/google_url_tracker_navigation_helper.h

 // 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.
 
 #ifndef CHROME_BROWSER_GOOGLE_GOOGLE_URL_TRACKER_NAVIGATION_HELPER_H_
 #define CHROME_BROWSER_GOOGLE_GOOGLE_URL_TRACKER_NAVIGATION_HELPER_H_
 
 class GoogleURLTracker;
 class InfoBarService;
 class Profile;
 
 namespace content {
 class NavigationController;
 }
 
 // A helper class for GoogleURLTracker that abstracts the details of listening
 // for various navigation events.
 class GoogleURLTrackerNavigationHelper {
  public:
   virtual ~GoogleURLTrackerNavigationHelper() {}
 
-  // Sets the GoogleURLTracker that should receive callbacks from this observer.
+  // Sets the GoogleURLTracker that is associated with this object.
   virtual void SetGoogleURLTracker(GoogleURLTracker* tracker) = 0;
 
-  // Enables or disables listening for navigation starts. OnNavigationPending
-  // will be called for each navigation start if listening is enabled.
-  virtual void SetListeningForNavigationStart(bool listen) = 0;
-
-  // Returns whether or not the observer is currently listening for navigation
-  // starts.
-  virtual bool IsListeningForNavigationStart() = 0;
-
   // Enables or disables listening for navigation commits for the given
   // NavigationController. OnNavigationCommitted will be called for each
   // navigation commit if listening is enabled.
   virtual void SetListeningForNavigationCommit(
       const content::NavigationController* nav_controller,
       bool listen) = 0;
 
   // Returns whether or not the observer is currently listening for navigation
   // commits for the given NavigationController.
   virtual bool IsListeningForNavigationCommit(
       const content::NavigationController* nav_controller) = 0;
 
   // Enables or disables listening for tab destruction for the given
   // NavigationController. OnTabClosed will be called on tab destruction if
   // listening is enabled.
   virtual void SetListeningForTabDestruction(
       const content::NavigationController* nav_controller,
       bool listen) = 0;
 
   // Returns whether or not the observer is currently listening for tab
   // destruction for the given NavigationController.
   virtual bool IsListeningForTabDestruction(
       const content::NavigationController* nav_controller) = 0;
 };
 
 #endif  // CHROME_BROWSER_GOOGLE_GOOGLE_URL_TRACKER_NAVIGATION_HELPER_H_