Force include test to run on every compile.

gyp/tools.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 file to build various tools.
 #
 # To build on Linux:
 #  ./gyp_skia tools.gyp && make tools
 #
 {
@@ skipping 448 matching lines @@
           '<(skia_include_path)/utils/SkJSONCPP.h',
           '<(skia_include_path)/views/SkOSWindow_Android.h',
           '<(skia_include_path)/views/SkOSWindow_iOS.h',
           '<(skia_include_path)/views/SkOSWindow_Mac.h',
           '<(skia_include_path)/views/SkOSWindow_SDL.h',
           '<(skia_include_path)/views/SkOSWindow_Unix.h',
           '<(skia_include_path)/views/SkOSWindow_Win.h',
           '<(skia_include_path)/views/SkWindow.h',
           '<(skia_include_path)/gpu/vk',
         ],
+        'output_file' : [
+          '<(INTERMEDIATE_DIR)/test_public_includes.cpp',
+        ],
       },
       'include_dirs': [
         '<@(includes_to_test)',
-        '../src/core',
       ],
       'sources': [
         # unused_param_test.cpp is generated by the action below.
         '<(INTERMEDIATE_DIR)/test_public_includes.cpp',
       ],
       'actions': [
         {
           'action_name': 'generate_includes_cpp',
           'inputs': [
             '../tools/generate_includes_cpp.py',
             '<@(includes_to_test)',
-            # This causes the gyp generator on mac to fail
-            #'<@(paths_to_ignore)',
           ],
           'outputs': [
-            '<(INTERMEDIATE_DIR)/test_public_includes.cpp',
+            '<@(output_file)',
+            # Force the script to always run so that we pick up when files have
+            # been deleted.
+            'filename_that_does_not_exists_but_forces_rebuild.txt',
           ],
           'action': ['python', '../tools/generate_includes_cpp.py',
                                '--ignore', '<(paths_to_ignore)',
-                               '<@(_outputs)', '<@(includes_to_test)'],
+                               '<@(output_file)', '<@(includes_to_test)'],
         },
       ],
     },
   ],
   'conditions': [
     ['skia_shared_lib',
       {
         'targets': [
           {
             'target_name': 'sklua',
@@ skipping 77 matching lines @@
               'flags.gyp:flags',
               'skia_lib.gyp:skia_lib',
               'resources',
             ],
           },
         ],
       },
     ],
   ],
 }