Make extensions use a correct same-origin check.

extensions/renderer/file_system_natives.cc

 // Copyright 2014 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/renderer/file_system_natives.h"
 
 #include <string>
 
 #include "extensions/common/constants.h"
 #include "extensions/renderer/script_context.h"
 #include "storage/common/fileapi/file_system_types.h"
 #include "storage/common/fileapi/file_system_util.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/web/WebDOMFileSystem.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
+#include "url/origin.h"
 
 namespace extensions {
 
 FileSystemNatives::FileSystemNatives(ScriptContext* context)
     : ObjectBackedNativeHandler(context) {
   RouteFunction(
       "GetFileEntry",
       base::Bind(&FileSystemNatives::GetFileEntry, base::Unretained(this)));
   RouteFunction("GetIsolatedFileSystem",
                 base::Bind(&FileSystemNatives::GetIsolatedFileSystem,
                            base::Unretained(this)));
   RouteFunction("CrackIsolatedFileSystemName",
                 base::Bind(&FileSystemNatives::CrackIsolatedFileSystemName,
                            base::Unretained(this)));
 }
 
 void FileSystemNatives::GetIsolatedFileSystem(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   CHECK(args.Length() == 1 || args.Length() == 2);
   CHECK(args[0]->IsString());
   std::string file_system_id(*v8::String::Utf8Value(args[0]));
   blink::WebLocalFrame* webframe =
       blink::WebLocalFrame::frameForContext(context()->v8_context());
   DCHECK(webframe);
 
   GURL context_url =
       extensions::ScriptContext::GetDataSourceURLForFrame(webframe);
   CHECK(context_url.SchemeIs(extensions::kExtensionScheme));
 
-  std::string name(storage::GetIsolatedFileSystemName(context_url.GetOrigin(),
-                                                      file_system_id));
+  const GURL origin = GURL(url::Origin(context_url).Serialize());

[brettw, 2016/02/03 19:12:38]

This would be better as:
  const GURL origin(url::Origin(context_url).Serialize());

[palmer, 2016/02/03 20:47:58]

Done.

+  std::string name(storage::GetIsolatedFileSystemName(origin, file_system_id));
 
   // The optional second argument is the subfolder within the isolated file
   // system at which to root the DOMFileSystem we're returning to the caller.
   std::string optional_root_name;
   if (args.Length() == 2) {
     CHECK(args[1]->IsString());
     optional_root_name = *v8::String::Utf8Value(args[1]);
   }
 
   GURL root_url(storage::GetIsolatedFileSystemRootURIString(
-      context_url.GetOrigin(), file_system_id, optional_root_name));
+      origin, file_system_id, optional_root_name));
 
   args.GetReturnValue().Set(
       blink::WebDOMFileSystem::create(webframe,
                                       blink::WebFileSystemTypeIsolated,
                                       blink::WebString::fromUTF8(name),
                                       root_url)
           .toV8Value(context()->v8_context()->Global(), args.GetIsolate()));
 }
 
 void FileSystemNatives::GetFileEntry(
@@ skipping 46 matching lines @@
   if (!storage::CrackIsolatedFileSystemName(filesystem_name, &filesystem_id))
     return;
 
   args.GetReturnValue().Set(v8::String::NewFromUtf8(args.GetIsolate(),
                                                     filesystem_id.c_str(),
                                                     v8::String::kNormalString,
                                                     filesystem_id.size()));
 }
 
 }  // namespace extensions