extensions: Register 'app' and 'webstore' bindings only if they are available.

extensions/common/permissions/permissions_data.cc

 // Copyright (c) 2013 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 "extensions/common/permissions/permissions_data.h"
 
 #include "base/command_line.h"
 #include "content/public/common/url_constants.h"
 #include "extensions/common/constants.h"
 #include "extensions/common/error_utils.h"
@@ skipping 59 matching lines @@
 
   return std::find(whitelist.begin(), whitelist.end(), extension->id()) !=
          whitelist.end();
 }
 
 // static
 bool PermissionsData::IsRestrictedUrl(const GURL& document_url,
                                       const GURL& top_frame_url,
                                       const Extension* extension,
                                       std::string* error) {
-  if (CanExecuteScriptEverywhere(extension))
+  if (extension && CanExecuteScriptEverywhere(extension))

[sadrul, 2014/08/06 18:51:51]

The null checks here are necessary since some tests send in a null extension to
IsAvailableToContext()

[not at google - send to devlin, 2014/08/06 22:10:28]

yeah this change is correct no matter what the context.

     return false;
 
   // Check if the scheme is valid for extensions. If not, return.
   if (!URLPattern::IsValidSchemeForExtensions(document_url.scheme()) &&
       document_url.spec() != url::kAboutBlankURL) {
     if (error) {
       *error = ErrorUtils::FormatErrorMessage(
                    manifest_errors::kCannotAccessPage,
                    document_url.spec());
     }
     return true;
   }
 
   if (!ExtensionsClient::Get()->IsScriptableURL(document_url, error))
     return true;
 
   bool allow_on_chrome_urls = base::CommandLine::ForCurrentProcess()->HasSwitch(
                                   switches::kExtensionsOnChromeURLs);
   if (document_url.SchemeIs(content::kChromeUIScheme) &&
       !allow_on_chrome_urls) {
     if (error)
       *error = manifest_errors::kCannotAccessChromeUrl;
     return true;
   }
 
-  if (top_frame_url.SchemeIs(kExtensionScheme) &&
-      top_frame_url.host() != extension->id() &&
-      !allow_on_chrome_urls) {
+  if (extension && top_frame_url.SchemeIs(kExtensionScheme) &&
+      top_frame_url.host() != extension->id() && !allow_on_chrome_urls) {
     if (error)
       *error = manifest_errors::kCannotAccessExtensionUrl;
     return true;
   }
 
   return false;
 }
 
 void PermissionsData::SetPermissions(
     const scoped_refptr<const PermissionSet>& active,
@@ skipping 241 matching lines @@
     return ACCESS_WITHHELD;
 
   if (error) {
     *error = ErrorUtils::FormatErrorMessage(manifest_errors::kCannotAccessPage,
                                             document_url.spec());
   }
   return ACCESS_DENIED;
 }
 
 }  // namespace extensions