Remove obsolete CityHash conditional.

gyp/tests.gyp

 # GYP file to build unit tests.
 {
   'includes': [
     'apptype_console.gypi',
   ],
   'targets': [
     {
       'target_name': 'tests',
       'type': 'executable',
       'include_dirs' : [
@@ skipping 141 matching lines @@
         'experimental.gyp:experimental',
         'pdf.gyp:pdf',
         'tools.gyp:picture_utils',
       ],
       'conditions': [
         [ 'skia_gpu == 1', {
           'include_dirs': [
             '../src/gpu',
           ],
         }],
-        [ 'skia_os == "nacl"', {
-          # CityHash is not supported on NaCl because the NaCl toolchain is
-          # missing byteswap.h which is needed by CityHash.
-          # TODO(borenet): Find a way to either provide this dependency or
-          # replace it.
-          'sources!': [
-            '../tests/BitmapHasherTest.cpp',
-            '../tests/ChecksumTest.cpp',
-          ],
-        }],
       ],
     },
   ],
 }
 
 # Local Variables:
 # tab-width:2
 # indent-tabs-mode:nil
 # End:
 # vim: set expandtab tabstop=2 shiftwidth=2: