Remove a redundant (duplicate) line in skia.gyp.

BUG=none
TEST=build with/without gtk (e.g. Linux and Win)

Review URL: http://codereview.chromium.org/7969015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@102086 0039d316-1c4b-4281-b951-d872f2087c98

skia/skia.gyp

@@ -793,7 +793,6 @@
             '../third_party/skia/src/ports/SkFontHost_FreeType.cpp',
             '../third_party/skia/src/ports/SkFontHost_TryeType_Tables.cpp',
             '../third_party/skia/src/ports/SkFontHost_gamma_none.cpp',
-            '../third_party/skia/src/ports/SkFontHost_gamma_none.cpp',
             '../third_party/skia/src/ports/SkFontHost_tables.cpp',
           ],
         }],