No need to include ../tools/flags in include_dirs when depending on flags target.

gyp/tools.gyp

 # GYP file to build various tools.
 #
 # To build on Linux:
 #  ./gyp_skia tools.gyp && make tools
 #
 {
   'includes': [
     'apptype_console.gypi',
   ],
   'targets': [
@@ skipping 141 matching lines @@
     },
     {
       'target_name': 'skpdiff',
       'type': 'executable',
       'sources': [
         '../tools/skpdiff/skpdiff_main.cpp',
         '../tools/skpdiff/SkDiffContext.cpp',
         '../tools/skpdiff/SkImageDiffer.cpp',
         '../tools/skpdiff/SkPMetric.cpp',
         '../tools/skpdiff/skpdiff_util.cpp',
-        '../tools/flags/SkCommandLineFlags.cpp',
       ],
       'include_dirs': [
-        '../tools/flags',
         '../src/core/', # needed for SkTLList.h
       ],
       'dependencies': [
+        'flags.gyp:flags',
         'skia_lib.gyp:skia_lib',
       ],
       'cflags': [
         '-O3',
       ],
       'conditions': [
         [ 'skia_os in ["linux", "freebsd", "openbsd", "solaris", "chromeos"]', {
           'link_settings': {
             'libraries': [
               '-lrt',
@@ skipping 96 matching lines @@
         'skia_lib.gyp:skia_lib',
       ],
     },
     {
       'target_name': 'skpinfo',
       'type': 'executable',
       'sources': [
         '../tools/skpinfo.cpp',
       ],
       'include_dirs': [
-        '../tools/flags',
         '../src/core/',
       ],
       'dependencies': [
         'flags.gyp:flags',
         'skia_lib.gyp:skia_lib',
       ],
     },
     {
       'target_name': 'gpuveto',
       'type': 'executable',
       'sources': [
         '../tools/gpuveto.cpp',
         '../tools/LazyDecodeBitmap.cpp',
       ],
       'include_dirs': [
         '../src/core/',
         '../src/images',
         '../src/lazy',
-        '../tools/flags',
       ],
       'dependencies': [
         'flags.gyp:flags',
         'skia_lib.gyp:skia_lib',
       ],
     },
     {
       'target_name': 'lua_app',
       'type': 'executable',
       'sources': [
@@ skipping 382 matching lines @@
             'type': 'executable',
             'sources': [
               '../tools/win_lcid.cpp',
             ],
           },
         ],
       },
     ],
   ],
 }