Convert skhello tool to SkFlags API.

gyp/tools.gyp

 # GYP file to build various tools.
 #
 # To build on Linux:
 #  ./gyp_skia tools.gyp && make tools
 #
 # Building on other platforms not tested yet.
 #
 {
   'includes': [
     'apptype_console.gypi',
@@ skipping 48 matching lines @@
         'skia_base_libs.gyp:skia_base_libs',
         'effects.gyp:effects',
         'images.gyp:images',
       ],
     },
     {
       'target_name': 'skhello',
       'type': 'executable',
       'sources': [
         '../tools/skhello.cpp',
+        '../tools/SkFlags.h',
+        '../tools/SkFlags.cpp',
       ],
       'dependencies': [
         'skia_base_libs.gyp:skia_base_libs',
         'effects.gyp:effects',
         'images.gyp:images',
       ],
     },
     {
       'target_name': 'skimage',
       'type': 'executable',
@@ skipping 152 matching lines @@
       ],
     },
   ],
 }
 
 # Local Variables:
 # tab-width:2
 # indent-tabs-mode:nil
 # End:
 # vim: set expandtab tabstop=2 shiftwidth=2: