Add a RWH_TabSwitchPaintDuration histogram.

chrome/browser/renderer_host/render_widget_host_view_gtk.cc

 // Copyright (c) 2006-2008 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/renderer_host/render_widget_host_view_gtk.h"
 
 // If this gets included after the gtk headers, then a bunch of compiler
 // errors happen because of a "#define Status int" in Xlib.h, which interacts
 // badly with URLRequestStatus::Status.
 #include "chrome/common/render_messages.h"
@@ skipping 358 matching lines @@
   // shrink down to the size of its child contents.
   gtk_window_set_resizable(GTK_WINDOW(popup), FALSE);
   gtk_window_move(GTK_WINDOW(popup), pos.x(), pos.y());
   gtk_widget_show_all(popup);
 }
 
 void RenderWidgetHostViewGtk::DidBecomeSelected() {
   if (!is_hidden_)
     return;
 
+  if (tab_switch_paint_time_.is_null())
+    tab_switch_paint_time_ = base::TimeTicks::Now();
   is_hidden_ = false;
   host_->WasRestored();
 }
 
 void RenderWidgetHostViewGtk::WasHidden() {
   if (is_hidden_)
     return;
 
   // If we receive any more paint messages while we are hidden, we want to
   // ignore them so we don't re-allocate the backing store.  We will paint
@@ skipping 199 matching lines @@
     }
     if (!whiteout_start_time_.is_null()) {
       base::TimeDelta whiteout_duration = base::TimeTicks::Now() -
           whiteout_start_time_;
       UMA_HISTOGRAM_TIMES("MPArch.RWHH_WhiteoutDuration", whiteout_duration);
 
       // Reset the start time to 0 so that we start recording again the next
       // time the backing store is NULL...
       whiteout_start_time_ = base::TimeTicks();
     }
+    if (!tab_switch_paint_time_.is_null()) {
+      base::TimeDelta tab_switch_paint_duration = base::TimeTicks::Now() -
+          tab_switch_paint_time_;
+      UMA_HISTOGRAM_TIMES("MPArch.RWH_TabSwitchPaintDuration",
+          tab_switch_paint_duration);
+      // Reset tab_switch_paint_time_ to 0 so future tab selections are
+      // recorded.
+      tab_switch_paint_time_ = base::TimeTicks();
+    }
   } else {
     if (window)
       gdk_window_clear(window);
     if (whiteout_start_time_.is_null())
       whiteout_start_time_ = base::TimeTicks::Now();
   }
 }
 
 void RenderWidgetHostViewGtk::ShowCurrentCursor() {
   // The widget may not have a window. If that's the case, abort mission. This
@@ skipping 51 matching lines @@
     const NativeWebKeyboardEvent& event) {
   if (!host_)
     return;
 
   EditCommands edit_commands;
   if (key_bindings_handler_->Match(event, &edit_commands)) {
     host_->ForwardEditCommandsForNextKeyEvent(edit_commands);
   }
   host_->ForwardKeyboardEvent(event);
 }