Report VideoDecoder status through ReadCB instead of through FilterHost.

media/base/filters.cc

Index: media/base/filters.cc
diff --git a/media/base/filters.cc b/media/base/filters.cc
index 910f1e7b8a437b2acd5c11ee438f41bcbf8892c1..5682be3c7d6cedfb1309e00d7a9567844756e9f5 100644
--- a/media/base/filters.cc
+++ b/media/base/filters.cc
@@ -61,6 +61,8 @@ VideoDecoder::VideoDecoder() {}
 
 VideoDecoder::~VideoDecoder() {}
 
+// TODO(xhwang): Remove the following four functions when VideoDecoder is not a
+// Filter any more. See bug: http://crbug.com/108340
 void VideoDecoder::Play(const base::Closure& /* callback */) {
   LOG(FATAL) << "VideoDecoder::Play is not supposed to be called.";
 }
@@ -74,6 +76,11 @@ void VideoDecoder::Seek(base::TimeDelta /* time */,
   LOG(FATAL) << "VideoDecoder::Seek is not supposed to be called.";
 }
 
+FilterHost* VideoDecoder::host() {
+  LOG(FATAL) << "VideoDecoder::host is not supposed to be called.";
+  return NULL;
+}
+
 bool VideoDecoder::HasAlpha() const {
   return false;
 }