Remove TabContents from TabStripModelObserver::ActiveTabChanged.

chrome/browser/ui/cocoa/tabs/tab_strip_model_observer_bridge.mm

Index: chrome/browser/ui/cocoa/tabs/tab_strip_model_observer_bridge.mm
diff --git a/chrome/browser/ui/cocoa/tabs/tab_strip_model_observer_bridge.mm b/chrome/browser/ui/cocoa/tabs/tab_strip_model_observer_bridge.mm
index c0c315c3001505844affa41af10bf77e8a8ce8eb..a95e8cefcdcbbcc97d713c8b7204a674197dc68d 100644
--- a/chrome/browser/ui/cocoa/tabs/tab_strip_model_observer_bridge.mm
+++ b/chrome/browser/ui/cocoa/tabs/tab_strip_model_observer_bridge.mm
@@ -60,16 +60,15 @@ void TabStripModelObserverBridge::TabDetachedAt(WebContents* contents,
   }
 }
 
-void TabStripModelObserverBridge::ActiveTabChanged(
-    TabContents* old_contents,
-    TabContents* new_contents,
-    int index,
-    bool user_gesture) {
+void TabStripModelObserverBridge::ActiveTabChanged(WebContents* old_contents,
+                                                   WebContents* new_contents,
+                                                   int index,
+                                                   bool user_gesture) {
   if ([controller_ respondsToSelector:
           @selector(activateTabWithContents:previousContents:atIndex:
                     userGesture:)]) {
-    [controller_ activateTabWithContents:WebContentsOf(new_contents)
-                        previousContents:WebContentsOf(old_contents)
+    [controller_ activateTabWithContents:new_contents
+                        previousContents:old_contents
                                  atIndex:index
                              userGesture:user_gesture];
   }