Refactor FFmpegURLProtocol code from FFmpegDemuxer into BlockingUrlProtocol.

media/filters/file_data_source.h

Index: media/filters/file_data_source.h
diff --git a/media/filters/file_data_source.h b/media/filters/file_data_source.h
index d5b81a4ce6af1146afda0f2955d255f37d16ab1c..a2c728de2407b9f6f074220b1aa72defc2716f75 100644
--- a/media/filters/file_data_source.h
+++ b/media/filters/file_data_source.h
@@ -7,7 +7,6 @@
 
 #include <string>
 
-#include "base/gtest_prod_util.h"
 #include "base/synchronization/lock.h"
 #include "media/base/data_source.h"
 
@@ -18,7 +17,6 @@ namespace media {
 class MEDIA_EXPORT FileDataSource : public DataSource {
  public:
   FileDataSource();
-  FileDataSource(bool disable_file_size);
 
   bool Initialize(const std::string& url);
 
@@ -31,6 +29,10 @@ class MEDIA_EXPORT FileDataSource : public DataSource {
   virtual bool IsStreaming() OVERRIDE;
   virtual void SetBitrate(int bitrate) OVERRIDE;
 
+  // Unit test helpers. Recreate the object if you want the default behaviour.
+  void force_read_errors_for_testing() { force_read_errors_ = true; }
+  void force_streaming_for_testing() { force_streaming_ = true; }
+
  protected:
   virtual ~FileDataSource();
 
@@ -44,17 +46,12 @@ class MEDIA_EXPORT FileDataSource : public DataSource {
   // Size of the file in bytes.
   int64 file_size_;
 
-  // True if the FileDataSource should ignore its set file size, false
-  // otherwise.
-  bool disable_file_size_;
-
-  // Critical section that protects all of the DataSource methods to prevent
-  // a Stop from happening while in the middle of a file I/O operation.
-  // TODO(ralphl): Ideally this would use asynchronous I/O or we will know
-  // that we will block for a short period of time in reads.  Otherwise, we can
-  // hang the pipeline Stop.
+  // Serialize all operations to prevent stopping during reads.
   base::Lock lock_;
 
+  bool force_read_errors_;
+  bool force_streaming_;
+
   DISALLOW_COPY_AND_ASSIGN(FileDataSource);
 };