Make the timestamp unroll offset consistent accross PES pids.

media/formats/mp2t/ts_section_pes.h

Index: media/formats/mp2t/ts_section_pes.h
diff --git a/media/formats/mp2t/ts_section_pes.h b/media/formats/mp2t/ts_section_pes.h
index b442ae491f37c72efb5a97512b797110b5ef51d5..d06cebac2f559ab073867c8faab0081c3565d217 100644
--- a/media/formats/mp2t/ts_section_pes.h
+++ b/media/formats/mp2t/ts_section_pes.h
@@ -15,10 +15,12 @@ namespace media {
 namespace mp2t {
 
 class EsParser;
+class TimestampUnroller;
 
 class TsSectionPes : public TsSection {
  public:
-  explicit TsSectionPes(scoped_ptr<EsParser> es_parser);
+  explicit TsSectionPes(scoped_ptr<EsParser> es_parser,
+                        TimestampUnroller* timestamp_unroller);
   virtual ~TsSectionPes();
 
   // TsSection implementation.
@@ -49,10 +51,7 @@ class TsSectionPes : public TsSection {
   bool wait_for_pusi_;
 
   // Used to unroll PTS and DTS.
-  bool previous_pts_valid_;
-  int64 previous_pts_;
-  bool previous_dts_valid_;
-  int64 previous_dts_;
+  TimestampUnroller* const timestamp_unroller_;
 
   DISALLOW_COPY_AND_ASSIGN(TsSectionPes);
 };