Add Blink side support for SourceBuffer.appendWindowStart & SourceBuffer.appendWindowEnd.

public/web/WebSourceBuffer.h

Index: public/web/WebSourceBuffer.h
diff --git a/public/web/WebSourceBuffer.h b/public/web/WebSourceBuffer.h
index 07c433a27893300918faa13927bce6807fa20227..6ccddbcd9deb5e9c21176b5fccdf38feda040d76 100644
--- a/public/web/WebSourceBuffer.h
+++ b/public/web/WebSourceBuffer.h
@@ -44,6 +44,8 @@ public:
     virtual void abort() = 0;
     virtual void remove(double start, double end) = 0;
     virtual bool setTimestampOffset(double) = 0;
+    virtual void setAppendWindowStart(double) = 0;

[jamesr, 2013/08/09 21:03:14]

the meaning of the parameter on these functions are not clear from the type. are
these timestamps? please clarify with either a parameter name or a comment

[changbin, 2013/08/09 23:00:32]

Done.

+    virtual void setAppendWindowEnd(double) = 0;
     virtual void removedFromMediaSource() = 0;
 };