disable [add folder] button for media galleries dialog if

chrome/browser/extensions/api/media_galleries/media_galleries_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.
 
 // Implements the Chrome Extensions Media Galleries API.
 
 #include "chrome/browser/extensions/api/media_galleries/media_galleries_api.h"
 
 #include <string>
 #include <vector>
 
 #include "base/platform_file.h"
 #include "base/values.h"
 #include "chrome/browser/media_gallery/media_file_system_registry.h"
 #include "chrome/browser/media_gallery/media_galleries_dialog_controller.h"
+#include "chrome/browser/ui/chrome_select_file_policy.h"
 #include "chrome/browser/ui/tab_contents/tab_contents.h"
 #include "chrome/common/extensions/api/experimental_media_galleries.h"
 #include "content/public/browser/child_process_security_policy.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 
 #if defined(OS_WIN)
 #include "base/sys_string_conversions.h"
 #endif
 
 using content::WebContents;
 
 namespace extensions {
 
 namespace {
 
 const char kInvalidInteractive[] = "Unknown value for interactive.";
 
+// Checks whether the MediaGalleries API is currently accessible (it may be
+// disallowed even if an extension has the requisite permission).
+bool ApiIsAccessible(std::string* error) {
+  if (!ChromeSelectFilePolicy::FileSelectDialogsAllowed()) {
+    *error = kDisallowedByPolicy;

[vandebo (ex-Chrome), 2012/08/21 23:24:20]

Is this constant defined somewhere?

[Evan Stade, 2012/08/21 23:56:17]

Done. Do you think we should call out the explicit policy?

[vandebo (ex-Chrome), 2012/08/22 00:01:51]

That might be nice.

[Evan Stade, 2012/08/22 00:31:53]

Done.

+    return false;
+  }
+
+  return true;
+}
+
 }  // namespace
 
 using chrome::MediaFileSystemRegistry;
 using content::ChildProcessSecurityPolicy;
 
 namespace MediaGalleries = extensions::api::experimental_media_galleries;
 namespace GetMediaFileSystems = MediaGalleries::GetMediaFileSystems;
 
 MediaGalleriesGetMediaFileSystemsFunction::
     ~MediaGalleriesGetMediaFileSystemsFunction() {}
 
 bool MediaGalleriesGetMediaFileSystemsFunction::RunImpl() {
+  if (!ApiIsAccessible(&error_))
+    return false;
+
   scoped_ptr<GetMediaFileSystems::Params> params(
       GetMediaFileSystems::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   MediaGalleries::GetMediaFileSystemsInteractivity interactive = "no";
   if (params->details.get() && params->details->interactive.get())
     interactive = *params->details->interactive;
 
   if (interactive == "yes") {
     ShowDialog();
     return true;
@@ skipping 58 matching lines @@
       base::Bind(&MediaGalleriesGetMediaFileSystemsFunction::ReturnGalleries,
                  this));
 }
 
 // MediaGalleriesAssembleMediaFileFunction -------------------------------------
 
 MediaGalleriesAssembleMediaFileFunction::
     ~MediaGalleriesAssembleMediaFileFunction() {}
 
 bool MediaGalleriesAssembleMediaFileFunction::RunImpl() {
+  if (!ApiIsAccessible(&error_))
+    return false;
+
   // TODO(vandebo) Update the metadata and return the new file.
   SetResult(Value::CreateNullValue());
   return true;
 }
 
 }  // namespace extensions