DO NOT MERGE Update libpng to 1.6.20
BUG:23265085
Change-Id: I85199805636d771f3597b691b63bc0bf46084833
(cherry picked from commit bbe98b40cda082024b669fa508931042eed18f82)
diff --git a/autogen.sh b/autogen.sh
index 9af34bd..9160717 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -73,12 +73,13 @@
# present bad things are happening.
#
# The autotools generated files:
-libpng_autotools_files="Makefile.in aclocal.m4 config.guess config.h.in\
- config.sub configure depcomp install-sh ltmain.sh missing test-driver"
+libpng_autotools_files="Makefile.in aclocal.m4 config.guess config.h.in
+ config.sub configure depcomp install-sh ltmain.sh missing\
+ test-driver"
#
# Files generated by versions of configue >2.68 or automake >1.13 (i.e. later
# versions than those required by configure.ac):
-libpng_autotools_extra="compile"
+libpng_autotools_extra="compile config.h.in~"
#
# These are separate because 'maintainer-clean' does not remove them.
libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\