Pipeline will execute a callback whenever an run-time error has happened.

media/base/pipeline_impl.cc

Index: media/base/pipeline_impl.cc
===================================================================
--- media/base/pipeline_impl.cc	(revision 22059)
+++ media/base/pipeline_impl.cc	(working copy)
@@ -247,6 +247,10 @@
   return error_;
 }
 
+void PipelineImpl::SetPipelineErrorCallback(PipelineCallback* error_callback) {
+  error_callback_.reset(error_callback);
+}
+
 void PipelineImpl::ResetState() {
   AutoLock auto_lock(lock_);
   const base::TimeDelta kZero;
@@ -551,6 +555,12 @@
 
   // Destroy every filter and reset the pipeline as well.
   DestroyFilters();
+
+  // If our owner has requested to be notified of an error, execute
+  // |error_callback_| unless we have a "good" error.
+  if (error_callback_.get() && error != PIPELINE_STOPPING) {
+    error_callback_->Run();
+  }
 }
 
 void PipelineImpl::PlaybackRateChangedTask(float playback_rate) {