Remove SK_BUILD_FOR SDL, BREW, and PALM.

gyp/utils.gyp

 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 # Gyp for utils.
 {
   'targets': [
     {
       'target_name': 'utils',
       'product_name': 'skia_utils',
@@ skipping 17 matching lines @@
         '../include/utils/unix',
         '../include/utils/win',
         '../src/core',
         '../src/image',
         '../src/opts',
         '../src/utils',
       ],
       'sources': [
         'utils.gypi', # Makes the gypi appear in IDEs (but does not modify the build).
       ],
-      'sources!': [
-          '../src/utils/SDL/SkOSWindow_SDL.cpp',
-      ],
       'conditions': [
         [ 'skia_os == "mac"', {
           'link_settings': {
             'libraries': [
               '$(SDKROOT)/System/Library/Frameworks/AGL.framework',
             ],
           },
         }],
         [ 'skia_os in ["mac", "ios"]', {
           'direct_dependent_settings': {
@@ skipping 86 matching lines @@
         '../src/utils/android/SkHwuiRenderer.cpp',
       ],
       'direct_dependent_settings': {
         'include_dirs': [
           '../src/utils/android',
         ],
       },
     },
   ],
 }