diff -up nss/coreconf/location.mk.iquote nss/coreconf/location.mk

--- nss/coreconf/location.mk.iquote	2017-07-27 16:09:32.000000000 +0200

+++ nss/coreconf/location.mk	2017-08-30 15:17:56.553361830 +0200

@@ -75,4 +75,9 @@ ifndef SQLITE_LIB_NAME

     SQLITE_LIB_NAME = sqlite3

 endif

+# Prefer in-tree headers over system headers

+ifdef IN_TREE_FREEBL_HEADERS_FIRST

+    INCLUDES += -iquote $(DIST)/../public/nss -iquote $(DIST)/../private/nss

+endif

+

 MK_LOCATION = included