Add custom default theme support and create a managed user default theme.

chrome/browser/themes/browser_theme_pack.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 "chrome/browser/themes/browser_theme_pack.h"
 
 #include <limits>
 
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 904 matching lines @@
     if (*img == prs_id)
       return true;
   }
 
   return false;
 }
 
 // private:
 
 BrowserThemePack::BrowserThemePack()
-    : header_(NULL),
+    : CustomThemeProvider(EXTENSION),
+      header_(NULL),
       tints_(NULL),
       colors_(NULL),
       display_properties_(NULL),
       source_images_(NULL) {
   scale_factors_ = ui::GetSupportedScaleFactors();
 }
 
 void BrowserThemePack::BuildHeader(const Extension* extension) {
   header_ = new BrowserThemePackHeader;
   header_->version = kThemePackVersion;
@@ skipping 668 matching lines @@
                                            false,
                                            &bitmap_data)) {
       NOTREACHED() << "Unable to encode theme image for prs_id="
                    << prs_id << " for scale_factor=" << scale_factors_[i];
       break;
     }
     image_memory_[scaled_raw_id] =
         base::RefCountedBytes::TakeVector(&bitmap_data);
   }
 }