chrome: Use stl utilities from the base namespace

chrome/browser/ui/views/tabs/window_finder_mus.cc

 // Copyright 2016 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/window_finder_mus.h"
 
 #include "ui/aura/window.h"
 #include "ui/views/mus/native_widget_mus.h"
 #include "ui/views/mus/window_manager_connection.h"
 
 WindowFinderMus::WindowFinderMus() {}
 
 WindowFinderMus::~WindowFinderMus() {}
 
 gfx::NativeWindow WindowFinderMus::GetLocalProcessWindowAtPoint(
     const gfx::Point& screen_point,
     const std::set<gfx::NativeWindow>& ignore) {
   std::set<ui::Window*> mus_windows =
       views::WindowManagerConnection::Get()->GetRoots();
   // TODO(erg): Needs to deal with stacking order here.
 
   // For every mus window, look at the associated aura window and see if we're
   // in that.
   for (ui::Window* mus : mus_windows) {
     views::Widget* widget = views::NativeWidgetMus::GetWidgetForWindow(mus);
     if (widget && widget->GetWindowBoundsInScreen().Contains(screen_point)) {
       aura::Window* content_window = widget->GetNativeWindow();
 
       // If we were instructed to ignore this window, ignore it.
-      if (ContainsKey(ignore, content_window))
+      if (base::ContainsKey(ignore, content_window))
         continue;
 
       return content_window;
     }
   }
 
   return nullptr;
 }