linux_aura: Keep GTK state from leaking between profiles.

chrome/browser/ui/cocoa/download/background_theme.mm

 // 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/cocoa/download/background_theme.h"
 
 #import "chrome/browser/themes/theme_properties.h"
 
 BackgroundTheme::BackgroundTheme(ui::ThemeProvider* provider) :
     provider_(provider) {
   NSColor* bgColor = [NSColor colorWithCalibratedRed:241/255.0
                                                green:245/255.0
                                                 blue:250/255.0
                                                alpha:77/255.0];
   NSColor* clickedColor = [NSColor colorWithCalibratedRed:239/255.0
                                                     green:245/255.0
                                                      blue:252/255.0
                                                     alpha:51/255.0];
 
   borderColor_.reset(
       [[NSColor colorWithCalibratedWhite:0 alpha:36/255.0] retain]);
   buttonGradient_.reset([[NSGradient alloc]
       initWithColors:[NSArray arrayWithObject:bgColor]]);
   buttonPressedGradient_.reset([[NSGradient alloc]
       initWithColors:[NSArray arrayWithObject:clickedColor]]);
 }
 
 BackgroundTheme::~BackgroundTheme() {}
 
+bool BackgroundTheme::UsingNativeTheme() const {
+  return true;
+}
+
 gfx::ImageSkia* BackgroundTheme::GetImageSkiaNamed(int id) const {
   return NULL;
 }
 
 SkColor BackgroundTheme::GetColor(int id) const {
   return SkColor();
 }
 
 int BackgroundTheme::GetDisplayProperty(int id) const {
   return -1;
@@ skipping 39 matching lines @@
       return buttonGradient_.get();
     case ThemeProperties::GRADIENT_TOOLBAR_BUTTON_PRESSED:
     case ThemeProperties::GRADIENT_TOOLBAR_BUTTON_PRESSED_INACTIVE:
       return buttonPressedGradient_.get();
     default:
       return provider_->GetNSGradient(id);
   }
 }