Transparent apps support

chrome/browser/extensions/api/app_window/app_window_api.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/extensions/api/app_window/app_window_api.h"
 
 #include "base/command_line.h"
 #include "base/time.h"
 #include "base/values.h"
 #include "chrome/browser/devtools/devtools_window.h"
@@ skipping 172 matching lines @@
               switches::kEnableExperimentalExtensionApis)) {
         create_params.frame = ShellWindow::FRAME_NONE;
         inject_html_titlebar = true;
       } else if (*options->frame == kNoneFrameOption) {
         create_params.frame = ShellWindow::FRAME_NONE;
       } else {
         create_params.frame = ShellWindow::FRAME_CHROME;
       }
     }
 
+    if (options->transparent_background.get() &&
+        CommandLine::ForCurrentProcess()->HasSwitch(
+            switches::kEnableExperimentalExtensionApis)) {
+      create_params.transparent_background = *options->transparent_background;
+    }
+
     gfx::Size& minimum_size = create_params.minimum_size;
     if (options->min_width.get())
       minimum_size.set_width(*options->min_width);
     if (options->min_height.get())
       minimum_size.set_height(*options->min_height);
     gfx::Size& maximum_size = create_params.maximum_size;
     if (options->max_width.get())
       maximum_size.set_width(*options->max_width);
     if (options->max_height.get())
       maximum_size.set_height(*options->max_height);
@@ skipping 31 matching lines @@
   if (ShellWindowRegistry::Get(profile())->HadDevToolsAttached(created_view)) {
     new DevToolsRestorer(this, created_view);
     return true;
   }
 
   SendResponse(true);
   return true;
 }
 
 }  // namespace extensions