Revert "Revert "remove kA1_Config, as it is no longer supported""

This reverts commit 36d712f2d4c5c79719280ad95523e6aaa88b068e.

BUG=
R=rmistry@google.com, mtklein@google.com

Author: reed@google.com

Review URL: https://codereview.chromium.org/86483002

git-svn-id: http://skia.googlecode.com/svn/trunk/gyp@12392 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/core.gypi b/core.gypi
index 54e23ef..530b118 100644
--- a/core.gypi
+++ b/core.gypi
@@ -44,7 +44,6 @@
         '<(skia_src_path)/core/SkBlitRow_D32.cpp',
         '<(skia_src_path)/core/SkBlitter.h',
         '<(skia_src_path)/core/SkBlitter.cpp',
-        '<(skia_src_path)/core/SkBlitter_A1.cpp',
         '<(skia_src_path)/core/SkBlitter_A8.cpp',
         '<(skia_src_path)/core/SkBlitter_ARGB32.cpp',
         '<(skia_src_path)/core/SkBlitter_RGB16.cpp',