Adding callback support to media filter Initialize() and Seek().

media/filters/file_data_source.cc

 // Copyright (c) 2009 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 "base/file_util.h"
 #include "base/string_util.h"
 #include "media/base/filter_host.h"
 #include "media/base/filters.h"
 #include "media/base/pipeline.h"
 #include "media/filters/file_data_source.h"
 
 namespace media {
 
 FileDataSource::FileDataSource()
     : file_(NULL),
       file_size_(0) {
 }
 
 FileDataSource::~FileDataSource() {
   Stop();
 }
 
-bool FileDataSource::Initialize(const std::string& url) {
+void FileDataSource::Initialize(const std::string& url,
+                                FilterCallback* callback) {
   DCHECK(!file_);
+  scoped_ptr<FilterCallback> c(callback);
 #if defined(OS_WIN)
   FilePath file_path(UTF8ToWide(url));
 #else
   FilePath file_path(url);
 #endif
   if (file_util::GetFileSize(file_path, &file_size_)) {
     file_ = file_util::OpenFile(file_path, "rb");
   }
   if (!file_) {
     file_size_ = 0;
     host()->Error(PIPELINE_ERROR_URL_NOT_FOUND);
-    return false;
+    callback->Run();
+    return;
   }
   media_format_.SetAsString(MediaFormat::kMimeType,
                             mime_type::kApplicationOctetStream);
   media_format_.SetAsString(MediaFormat::kURL, url);
   host()->SetTotalBytes(file_size_);
   host()->SetBufferedBytes(file_size_);
-  host()->InitializationComplete();
-  return true;
+  callback->Run();
 }
 
 void FileDataSource::Stop() {
   AutoLock l(lock_);
   if (file_) {
     file_util::CloseFile(file_);
     file_ = NULL;
     file_size_ = 0;
   }
 }
@@ skipping 55 matching lines @@
   *size_out = file_size_;
   return (NULL != file_);
 }
 
 bool FileDataSource::IsSeekable() {
   // A file data source is always seekable.
   return true;
 }
 
 }  // namespace media