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

media/filters/file_data_source.cc

Index: media/filters/file_data_source.cc
diff --git a/media/filters/file_data_source.cc b/media/filters/file_data_source.cc
index 2e13a59e9bcfb75515e6ae5e4cce7eb3ac595edc..8ac44998fd24e6e203c086af8713ecbb5c29a482 100644
--- a/media/filters/file_data_source.cc
+++ b/media/filters/file_data_source.cc
@@ -20,8 +20,10 @@ 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
@@ -33,15 +35,15 @@ bool FileDataSource::Initialize(const std::string& url) {
   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() {