Remove all remaining traces of MessageLoopProxy.

components/nacl/loader/nacl_listener.cc

Index: components/nacl/loader/nacl_listener.cc
diff --git a/components/nacl/loader/nacl_listener.cc b/components/nacl/loader/nacl_listener.cc
index 66f967178fe7f22a84aba89258dcc6f483a11955..5b6291158c1d8cd7d12964c3d9fec4d5e8450d68 100644
--- a/components/nacl/loader/nacl_listener.cc
+++ b/components/nacl/loader/nacl_listener.cc
@@ -101,7 +101,7 @@ void DebugStubPortSelectedHandler(uint16_t port) {
 
 // Creates the PPAPI IPC channel between the NaCl IRT and the host
 // (browser/renderer) process, and starts to listen it on the thread where
-// the given message_loop_proxy runs.
+// the given task runner runs.
 // Also, creates and sets the corresponding NaClDesc to the given nap with
 // the FD #.
 void SetUpIPCAdapter(