Revert 285479 "Make DataSource::Stop() synchronous."

trunk/src/content/renderer/media/buffered_data_source_unittest.cc

Index: trunk/src/content/renderer/media/buffered_data_source_unittest.cc
===================================================================
--- trunk/src/content/renderer/media/buffered_data_source_unittest.cc	(revision 285857)
+++ trunk/src/content/renderer/media/buffered_data_source_unittest.cc	(working copy)
@@ -178,7 +178,7 @@
       message_loop_.RunUntilIdle();
     }
 
-    data_source_->Stop();
+    data_source_->Stop(media::NewExpectedClosure());
     message_loop_.RunUntilIdle();
   }
 
@@ -505,6 +505,31 @@
   Stop();
 }
 
+static void SetTrue(bool* value) {
+  *value = true;
+}
+
+// This test makes sure that Stop() does not require a task to run on
+// |message_loop_| before it calls its callback. This prevents accidental
+// introduction of a pipeline teardown deadlock. The pipeline owner blocks
+// the render message loop while waiting for Stop() to complete. Since this
+// object runs on the render message loop, Stop() will not complete if it
+// requires a task to run on the the message loop that is being blocked.
+TEST_F(BufferedDataSourceTest, StopDoesNotUseMessageLoopForCallback) {
+  InitializeWith206Response();
+
+  // Stop() the data source, using a callback that lets us verify that it was
+  // called before Stop() returns. This is to make sure that the callback does
+  // not require |message_loop_| to execute tasks before being called.
+  bool stop_done_called = false;
+  EXPECT_TRUE(data_source_->loading());
+  data_source_->Stop(base::Bind(&SetTrue, &stop_done_called));
+
+  // Verify that the callback was called inside the Stop() call.
+  EXPECT_TRUE(stop_done_called);
+  message_loop_.RunUntilIdle();
+}
+
 TEST_F(BufferedDataSourceTest, StopDuringRead) {
   InitializeWith206Response();
 
@@ -516,7 +541,7 @@
   {
     InSequence s;
     EXPECT_CALL(*this, ReadCallback(media::DataSource::kReadError));
-    data_source_->Stop();
+    data_source_->Stop(media::NewExpectedClosure());
   }
   message_loop_.RunUntilIdle();
 }