Tighten up media::DecoderBuffer API contract for end of stream buffers (round 2).

media/base/stream_parser_buffer.cc

Index: media/base/stream_parser_buffer.cc
diff --git a/media/base/stream_parser_buffer.cc b/media/base/stream_parser_buffer.cc
index 13e649e8595df8b152da7d51f159a75987886490..547cf27748dd5698d3fb1f3c2184becec741eac4 100644
--- a/media/base/stream_parser_buffer.cc
+++ b/media/base/stream_parser_buffer.cc
@@ -35,7 +35,12 @@ StreamParserBuffer::StreamParserBuffer(const uint8* data, int data_size,
       is_keyframe_(is_keyframe),
       decode_timestamp_(kNoTimestamp()),
       config_id_(kInvalidConfigId) {
-  SetDuration(kNoTimestamp());
+  // TODO(scherkus): Should DataBuffer constructor accept a timestamp and
+  // duration to force clients to set them? Today they end up being zero which
+  // is both a common and valid value and could lead to bugs.
+  if (data) {
+    SetDuration(kNoTimestamp());
+  }
 }
 
 StreamParserBuffer::~StreamParserBuffer() {