Add follow up TODO from previous CL.

Bug: 161549994
Test: Compile (comment change only)
Change-Id: Idf815d10868061d776c732ffdae06397022fe097
diff --git a/services/mediatranscoding/MediaTranscodingService.cpp b/services/mediatranscoding/MediaTranscodingService.cpp
index 6ae630f..ef7d6d2 100644
--- a/services/mediatranscoding/MediaTranscodingService.cpp
+++ b/services/mediatranscoding/MediaTranscodingService.cpp
@@ -71,6 +71,7 @@
 binder_status_t MediaTranscodingService::dump(int fd, const char** /*args*/, uint32_t /*numArgs*/) {
     String8 result;
 
+    // TODO(b/161549994): Remove libbinder dependencies for mainline.
     if (checkCallingPermission(String16("android.permission.DUMP")) == false) {
         result.format(
                 "Permission Denial: "