gimp-gap-devel: update to version 2.7.0 git master as of 20180318

Remove unnecessary build dependency on git.

graphics/gimp-gap-devel/Portfile

@@ -6,8 +6,8 @@ PortGroup       active_variants 1.1
 name            gimp-gap-devel
 conflicts       gimp-gap
 set git_name    gimp-gap
-set git_commit  dc902cc25d103e5602a114f69a6932587cf3ea52
-set git_date    20151108
+set git_commit  6c7ce40a4f74fe08b1607465758c658006b4b12f
+set git_date    20180318
 version         2.7.0-${git_date}
 license         GPL-2+
 categories      graphics
@@ -32,23 +32,24 @@ master_sites    https://git.gnome.org/browse/${git_name}/snapshot/
 
 distname        ${git_name}-${git_commit}
 
-checksums       rmd160  a400caec0a761d2fc74f6dc6f30707d6b8ad1d21 \
-                sha256  9e628bd896b7a33c7445ef32d46a212817877e43b5f89a91eb96b24e118b6cfb
+checksums       rmd160  efb79db1b5527ecbe52aca6b0d79b429132fdfa2 \
+                sha256  adbe097ce6089f7b595014b617ce448f2a3355cce264028794be15093139ee90 \
+                size    13417307
 
-pre-patch       {
+post-extract    {
                     system "cd ${worksrcpath}/extern_libs && gzip -dc ffmpeg.tar.gz | tar -xf -"
                 }
 
 patchfiles      patch-extern_libs-configure_options_ffmpeg.txt.diff \
-                patch-automake-1.13.diff
+                patch-automake-1.13.diff \
+                patch-gap_colordiff.c.diff
 
 post-patch     {
                    set ffmpeg_extras "--cc=${configure.cc} --arch=${build_arch}"
                    reinplace "s|MP_FFMPEG_EXTRAS|${ffmpeg_extras}|" ${worksrcpath}/extern_libs/configure_options_ffmpeg.txt
                }
 
-depends_build   port:git \
-                port:pkgconfig \
+depends_build   port:pkgconfig \
                 port:autoconf \
                 port:automake \
                 port:intltool \

graphics/gimp-gap-devel/files/patch-gap_colordiff.c.diff

@@ -0,0 +1,22 @@
+--- gap/gap_colordiff.c.orig	2018-03-22 12:44:19.000000000 -0700
++++ gap/gap_colordiff.c	2018-03-22 12:46:38.000000000 -0700
+@@ -635,7 +635,7 @@
+   gdouble delta_L_prime = lab2.L - lab1.L;
+   gdouble delta_C_prime = C_prime_2 - C_prime_1;
+
+-  gdouble h_bar = abs(h_prime_1 - h_prime_2);
++  gdouble h_bar = fabs(h_prime_1 - h_prime_2);
+   gdouble delta_h_prime;
+   if (C_prime_1 * C_prime_2 == 0) delta_h_prime = 0;
+   else
+@@ -681,8 +681,8 @@
+   gdouble L_prime_average_minus_50_square = (L_prime_average - 50);
+   L_prime_average_minus_50_square *= L_prime_average_minus_50_square;
+
+-  gdouble S_L = 1 + ((.015d * L_prime_average_minus_50_square) / sqrt(20 + L_prime_average_minus_50_square));
+-  gdouble S_C = 1 + .045d * C_prime_average;
++  gdouble S_L = 1 + ((.015 * L_prime_average_minus_50_square) / sqrt(20 + L_prime_average_minus_50_square));
++  gdouble S_C = 1 + .045 * C_prime_average;
+   gdouble T = 1
+       - .17 * cos(gimp_deg_to_rad(h_prime_average - 30))
+       + .24 * cos(gimp_deg_to_rad(h_prime_average * 2))