Revert 166085 - Selective build clobbering feature (landmines.py and android build scripts).

build/gyp_chromium

 #!/usr/bin/env python
 
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This script is wrapper for Chromium that adds some support for how GYP
 # is invoked by Chromium beyond what can be done in the gclient hooks.
 
 import glob
-import gyp_helper
 import os
 import shlex
 import subprocess
 import sys
 
 script_dir = os.path.dirname(os.path.realpath(__file__))
 chrome_src = os.path.abspath(os.path.join(script_dir, os.pardir))
 
 sys.path.insert(0, os.path.join(chrome_src, 'tools', 'gyp', 'pylib'))
 import gyp
@@ skipping 16 matching lines @@
 # may not be worth it).
 if sys.platform == 'win32':
   try:
     sys.path.insert(0, os.path.join(chrome_src, 'third_party', 'psyco_win32'))
     import psyco
   except:
     psyco = None
 else:
   psyco = None
 
+def apply_gyp_environment(file_path=None):
+  """
+  Reads in a *.gyp_env file and applies the valid keys to os.environ.
+  """
+  if not file_path or not os.path.exists(file_path):
+    return
+  file_contents = open(file_path).read()
+  try:
+    file_data = eval(file_contents, {'__builtins__': None}, None)
+  except SyntaxError, e:
+    e.filename = os.path.abspath(file_path)
+    raise
+  supported_vars = ( 'CC',
+                     'CHROMIUM_GYP_FILE',
+                     'CHROMIUM_GYP_SYNTAX_CHECK',
+                     'CXX',
+                     'GYP_DEFINES',
+                     'GYP_GENERATOR_FLAGS',
+                     'GYP_GENERATOR_OUTPUT',
+                     'GYP_GENERATORS', )
+  for var in supported_vars:
+    val = file_data.get(var)
+    if val:
+      if var in os.environ:
+        print 'INFO: Environment value for "%s" overrides value in %s.' % (
+            var, os.path.abspath(file_path)
+        )
+      else:
+        os.environ[var] = val
+
 def additional_include_files(args=[]):
   """
   Returns a list of additional (.gypi) files to include, without
   duplicating ones that are already specified on the command line.
   """
   # Determine the include files specified on the command line.
   # This doesn't cover all the different option formats you can use,
   # but it's mainly intended to avoid duplicating flags on the automatic
   # makefile regeneration which only uses this format.
   specified_includes = set()
@@ skipping 30 matching lines @@
   if sys.platform == 'cygwin':
     python_dir = os.path.join(chrome_src, 'third_party', 'python_26')
     env = os.environ.copy()
     env['PATH'] = python_dir + os.pathsep + env.get('PATH', '')
     p = subprocess.Popen(
        [os.path.join(python_dir, 'python.exe')] + sys.argv,
        env=env, shell=False)
     p.communicate()
     sys.exit(p.returncode)
 
-  gyp_helper.apply_chromium_gyp_env()
+  if 'SKIP_CHROMIUM_GYP_ENV' not in os.environ:
+    # Update the environment based on chromium.gyp_env
+    gyp_env_path = os.path.join(os.path.dirname(chrome_src), 'chromium.gyp_env')
+    apply_gyp_environment(gyp_env_path)
 
   # This could give false positives since it doesn't actually do real option
   # parsing.  Oh well.
   gyp_file_specified = False
   for arg in args:
     if arg.endswith('.gyp'):
       gyp_file_specified = True
       break
 
   # If we didn't get a file, check an env var, and then fall back to
@@ skipping 25 matching lines @@
   # to enfore syntax checking.
   syntax_check = os.environ.get('CHROMIUM_GYP_SYNTAX_CHECK')
   if syntax_check and int(syntax_check):
     args.append('--check')
 
   print 'Updating projects from gyp files...'
   sys.stdout.flush()
 
   # Off we go...
   sys.exit(gyp.main(args))