Add UMA for first app list paint on Windows.

ui/app_list/views/app_list_view.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 "ui/app_list/views/app_list_view.h"
 
+#include "base/callback.h"
 #include "base/command_line.h"
 #include "base/strings/string_util.h"
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/app_list_model.h"
 #include "ui/app_list/app_list_view_delegate.h"
 #include "ui/app_list/pagination_model.h"
 #include "ui/app_list/signin_delegate.h"
 #include "ui/app_list/views/app_list_background.h"
 #include "ui/app_list/views/app_list_main_view.h"
 #include "ui/app_list/views/search_box_view.h"
@@ skipping 13 matching lines @@
 #include "ui/aura/root_window.h"
 #if defined(OS_WIN)
 #include "ui/base/win/shell.h"
 #endif
 #endif
 
 namespace app_list {
 
 namespace {
 
+base::Closure g_next_paint_callback;
+
 // The distance between the arrow tip and edge of the anchor view.
 const int kArrowOffset = 10;
 
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 // AppListView:
 
 AppListView::AppListView(AppListViewDelegate* delegate)
     : model_(new AppListModel),
@@ skipping 106 matching lines @@
 }
 
 void AppListView::UpdateBounds() {
   SizeToContents();
 }
 
 gfx::Size AppListView::GetPreferredSize() {
   return app_list_main_view_->GetPreferredSize();
 }
 
+void AppListView::Paint(gfx::Canvas* canvas) {
+  views::BubbleDelegateView::Paint(canvas);
+  if (!g_next_paint_callback.is_null()) {
+    g_next_paint_callback.Run();
+    g_next_paint_callback.Reset();
+  }
+}
+
 bool AppListView::ShouldHandleSystemCommands() const {
   return true;
 }
 
 void AppListView::Prerender() {
   app_list_main_view_->Prerender();
 }
 
 void AppListView::OnSigninStatusChanged() {
   signin_view_->SetVisible(!model_->signed_in());
   app_list_main_view_->SetVisible(model_->signed_in());
   app_list_main_view_->search_box_view()->InvalidateMenu();
 }
 
 void AppListView::AddObserver(Observer* observer) {
   observers_.AddObserver(observer);
 }
 
 void AppListView::RemoveObserver(Observer* observer) {
   observers_.RemoveObserver(observer);
 }
 
+// static
+void AppListView::SetNextPaintCallback(const base::Closure& callback) {
+  g_next_paint_callback = callback;
+}
+
 #if defined(OS_WIN)
 HWND AppListView::GetHWND() const {
 #if defined(USE_AURA)
   gfx::NativeWindow window =
       GetWidget()->GetTopLevelWidget()->GetNativeWindow();
   return window->GetRootWindow()->GetAcceleratedWidget();
 #else
   return GetWidget()->GetTopLevelWidget()->GetNativeWindow();
 #endif
 }
@@ skipping 79 matching lines @@
 
 void AppListView::OnAppListModelSigninStatusChanged() {
   OnSigninStatusChanged();
 }
 
 void AppListView::OnAppListModelCurrentUserChanged() {
   OnSigninStatusChanged();
 }
 
 }  // namespace app_list