Convert Filter::Seek() to use new callback system.

media/base/pipeline_impl.cc

Index: media/base/pipeline_impl.cc
diff --git a/media/base/pipeline_impl.cc b/media/base/pipeline_impl.cc
index d7ad574b3ad02c19d212960691e2d40a32bb5d5a..80e0a00fa3a3d2d1b467f3336419bdfc5fe8761e 100644
--- a/media/base/pipeline_impl.cc
+++ b/media/base/pipeline_impl.cc
@@ -9,6 +9,7 @@
 
 #include <algorithm>
 
+#include "base/bind.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/stl_util-inl.h"
@@ -575,6 +576,13 @@ void PipelineImpl::OnFilterStateTransition() {
       NewRunnableMethod(this, &PipelineImpl::FilterStateTransitionTask));
 }
 
+// Called from any thread.
+void PipelineImpl::OnFilterStateTransitionWithStatus(PipelineStatus status) {
+  if (status != PIPELINE_OK)
+    SetError(status);

[Ami GONE FROM CHROMIUM, 2011/05/12 20:42:16]

This is funky b/c it posts the errorchanged task, and then OFST() below posts a
FSTT task, which depends on the errorchanged having run.  I guess this is ok
(messageloop must guarantee order of execution, right?), but funky.

[acolwell GONE FROM CHROMIUM, 2011/05/12 22:30:40]

Yes. This is one of the major reasons why I want to get rid of SetError() in
FilterHost. Code depends on this fact that both the callback AND the error get
put on the message loop. A few months ago, I tried to prevent posting to the
message loop if we were on the pipeline thread, but ran into this assumption.

+  OnFilterStateTransition();
+}
+
 void PipelineImpl::OnTeardownStateTransition() {
   message_loop_->PostTask(FROM_HERE,
       NewRunnableMethod(this, &PipelineImpl::TeardownStateTransitionTask));
@@ -710,8 +718,9 @@ void PipelineImpl::InitializeTask() {
     seek_pending_ = true;
     set_state(kSeeking);
     seek_timestamp_ = base::TimeDelta();
-    pipeline_filter_->Seek(seek_timestamp_,
-        NewCallback(this, &PipelineImpl::OnFilterStateTransition));
+    pipeline_filter_->Seek(
+        seek_timestamp_,
+        base::Bind(&PipelineImpl::OnFilterStateTransitionWithStatus, this));
   }
 }
 
@@ -952,7 +961,7 @@ void PipelineImpl::FilterStateTransitionTask() {
           NewCallback(this, &PipelineImpl::OnFilterStateTransition));
     } else if (state_ == kSeeking) {
       pipeline_filter_->Seek(seek_timestamp_,
-          NewCallback(this, &PipelineImpl::OnFilterStateTransition));
+          base::Bind(&PipelineImpl::OnFilterStateTransitionWithStatus, this));
     } else if (state_ == kStarting) {
       pipeline_filter_->Play(
           NewCallback(this, &PipelineImpl::OnFilterStateTransition));