GTK Theme: Don't render IDR_THEME_TOOLBAR on GtkWidgets.

chrome/browser/gtk/browser_toolbar_gtk.cc

 // Copyright (c) 2009 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/gtk/browser_toolbar_gtk.h"
 
 #include <gdk/gdkkeysyms.h>
 #include <X11/XF86keysym.h>
 
 #include "app/gtk_dnd_util.h"
@@ skipping 515 matching lines @@
   old_menu->Cancel();
   gtk_chrome_button_set_paint_state(GTK_CHROME_BUTTON(relevant_button),
                                     GTK_STATE_ACTIVE);
   new_menu->Popup(relevant_button, 0, timestamp);
 }
 
 // static
 gboolean BrowserToolbarGtk::OnAlignmentExpose(GtkWidget* widget,
                                               GdkEventExpose* e,
                                               BrowserToolbarGtk* toolbar) {
+  // We don't need to render the toolbar image in GTK mode.
+  if (toolbar->theme_provider_->UseGtkTheme())
+    return FALSE;
+
   cairo_t* cr = gdk_cairo_create(GDK_DRAWABLE(widget->window));
   cairo_rectangle(cr, e->area.x, e->area.y, e->area.width, e->area.height);
   cairo_clip(cr);
   // The toolbar is supposed to blend in with the active tab, so we have to pass
   // coordinates for the IDR_THEME_TOOLBAR bitmap relative to the top of the
   // tab strip.
   gfx::Point tabstrip_origin =
       toolbar->window_->tabstrip()->GetTabStripOriginForWidget(widget);
   GtkThemeProvider* theme_provider = toolbar->theme_provider_;
   GdkPixbuf* toolbar_background = theme_provider->GetPixbufNamed(
@@ skipping 166 matching lines @@
       g_signal_stop_emission_by_name(menu, "move-current");
     default:
       break;
   }
 }
 
 bool BrowserToolbarGtk::ShouldOnlyShowLocation() const {
   // If we're a popup window, only show the location bar (omnibox).
   return browser_->type() != Browser::TYPE_NORMAL;
 }