Eliminate build differences in nacl gated on nacl_standalone.

build/gyp_nacl

 #!/usr/bin/python
 
 # This script is wrapper for NaCl that adds some support for how GYP
 # is invoked by NaCl beyond what can be done it the gclient hooks.
 
 import glob
 import os
 import shlex
 import sys
 
-print 'Updating projects from gyp files...'
+script_dir = os.path.dirname(os.path.abspath(__file__))
+chrome_src = os.path.abspath(os.path.join(script_dir, os.pardir, os.pardir))
 
-try:
-  import gyp
-except ImportError, e:
-  sys.path.append(os.path.join(os.path.dirname(sys.argv[0]),
-                               '..', '..', 'tools', 'gyp', 'pylib'))
-  import gyp
+sys.path.insert(0, os.path.join(chrome_src, 'tools', 'gyp', 'pylib'))
+import gyp
+
+
+# Add paths so that pymod_do_main(...) can import files.
+sys.path.insert(1, os.path.join(script_dir))
+
 
 if __name__ == '__main__':
   args = sys.argv[1:]
 
   # If we didn't get a file, check an env var, and then fall back to
   # assuming 'src/build/all.gyp'
   if len(args) == 0:
-    args += shlex.split(os.environ.get('NACL_GYP_FILE',
-                                       'native_client/build/all.gyp'))
+    args += shlex.split(os.environ.get(
+        'NACL_GYP_FILE',
+        os.path.join(script_dir, 'all.gyp').replace('\\', '/')))
 
-  # Add in configs.gypi
-  args += ['-I', 'native_client/build/configs.gypi']
+  # Add in common.gypi
+  args += ['-I', os.path.join(chrome_src,
+                              'build/common.gypi').replace('\\', '/')]
 
   # Pick depth explicitly.
-  args += ['--depth', '.']
+  args += ['--depth', chrome_src]
 
   # Building NaCl as standalone (not as part of Chrome)
   args += ['-D', 'nacl_standalone=1']
 
+  print 'Updating projects from gyp files...'
+  sys.stdout.flush()
+
   # Off we go...
   sys.exit(gyp.main(args))