Added the Ash.Tab.TimeBetweenSwitchToExistingTabUserActions histogram to track time between tab swit

chrome/browser/ui/views/tabs/tab_strip.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 "chrome/browser/ui/views/tabs/tab_strip.h"
 
 #if defined(OS_WIN)
 #include <windowsx.h>
 #endif
 
@@ skipping 2611 matching lines @@
   // Add an observer so we know when the mouse moves out of the tabstrip.
   if (reset_to_shrink_on_exit_)
     AddMessageLoopObserver();
   else
     RemoveMessageLoopObserver();
 }
 
 void TabStrip::ButtonPressed(views::Button* sender, const ui::Event& event) {
   if (sender == newtab_button_) {
     content::RecordAction(UserMetricsAction("NewTab_Button"));
+    // TODO(bruthig):
     UMA_HISTOGRAM_ENUMERATION("Tab.NewTab", TabStripModel::NEW_TAB_BUTTON,
                               TabStripModel::NEW_TAB_ENUM_COUNT);
     if (event.IsMouseEvent()) {
       const ui::MouseEvent& mouse = static_cast<const ui::MouseEvent&>(event);
       if (mouse.IsOnlyMiddleMouseButton()) {
         base::string16 clipboard_text = GetClipboardText();
         if (!clipboard_text.empty())
           controller()->CreateNewTabWithLocation(clipboard_text);
         return;
       }
@@ skipping 86 matching lines @@
       break;
 
     case ui::ET_GESTURE_TAP: {
       const int active_index = controller_->GetActiveIndex();
       DCHECK_NE(-1, active_index);
       Tab* active_tab = tab_at(active_index);
       TouchUMA::GestureActionType action = TouchUMA::GESTURE_TABNOSWITCH_TAP;
       if (active_tab->tab_activated_with_last_tap_down())
         action = TouchUMA::GESTURE_TABSWITCH_TAP;
       TouchUMA::RecordGestureAction(action);
+      // TODO(bruthig):
       break;
     }
 
     default:
       break;
   }
   event->SetHandled();
 }
 
 views::View* TabStrip::TargetForRect(views::View* root, const gfx::Rect& rect) {
@@ skipping 19 matching lines @@
           ConvertPointToViewAndGetEventHandler(this, newtab_button_, point);
       if (view)
         return view;
     }
     Tab* tab = FindTabForEvent(point);
     if (tab)
       return ConvertPointToViewAndGetEventHandler(this, tab, point);
   }
   return this;
 }