Use -Werror in external/libvterm am: 3210a80411 am: 4687070036 am: bd0994e30e
am: dcdd338eba

Change-Id: Iaee2ec4803440d7dfb4971f9c0c038d1de6c51b4
diff --git a/Android.bp b/Android.bp
index b09fd43..33d3b75 100644
--- a/Android.bp
+++ b/Android.bp
@@ -16,8 +16,11 @@
 
     cflags: [
         "-std=c99",
+        "-Wall",
+        "-Werror",
         "-Wno-missing-field-initializers",
         "-Wno-sign-compare",
+        "-Wno-unused-function",
         "-Wno-unused-parameter",
     ],
 }