[NaCl SDK] Don't include gtest/gmock in library form

native_client_sdk/src/tests/nacl_io_socket_test/example.dsc

 {
   'TOOLS': ['clang-newlib', 'glibc', 'pnacl', 'linux', 'mac'],
   'TARGETS': [
     {
       'NAME' : 'nacl_io_socket_test',
       'TYPE' : 'main',
       'SOURCES' : [
         'main.cc',
         'socket_test.cc',
         'echo_server.cc',
         'echo_server.h',
       ],
       'DEPS': ['ppapi_simple_cpp', 'nacl_io'],
-      'LIBS': ['ppapi_simple_cpp', 'ppapi_cpp', 'gmock', 'ppapi', 'gtest', 'nacl_io', 'pthread'],
+      'LIBS': ['ppapi_simple_cpp', 'ppapi_cpp', 'ppapi', 'nacl_io', 'pthread'],
+      'EXTRA_SOURCES' : ['../../src/gtest/src/gtest-all.cc'],
+      'INCLUDES': [
+        '../../src/gtest/include',
+        '../../src/gtest'
+      ],
       'CXXFLAGS': ['-Wno-sign-compare']
     }
   ],
   'DATA': [
     'example.js'
   ],
   'DEST': 'tests',
   'NAME': 'nacl_io_socket_test',
   'TITLE': 'NaCl IO Socket test',
   'SOCKET_PERMISSIONS': [
     "tcp-listen:*:*",
     "tcp-connect",
     "resolve-host",
     "udp-bind:*:*",
     "udp-send-to:*:*"
   ]
 }