Add default -Werror to libstagefright/codecs.

Bug: 66996870
Test: normal build
Change-Id: I16c1d3b4b7ab3679b12dd0d94e5d130e33a27009
diff --git a/cc/config/global.go b/cc/config/global.go
index aacd383..6f4b3e2 100644
--- a/cc/config/global.go
+++ b/cc/config/global.go
@@ -122,7 +122,6 @@
 	WarningAllowedProjects = []string{
 		"external/skia/",
 		"device/",
-		"frameworks/av/media/libstagefright/codecs/",
 		"vendor/",
 	}