Remove GYP_DEFINE reference in clang update.py

Bug: 756686, 873373
Change-Id: I22adc1b01841e97a81e230f4fa8b94e96fdf623a
Reviewed-on: https://chromium-review.googlesource.com/c/1309229
Commit-Queue: Stephen Martinis <martiniss@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#604387}

DEPS

@@ -49,6 +49,11 @@ vars = {
   # purposes.
   'checkout_configuration': 'default',
 
+  # By default, don't check out android. Will be overridden by gclient
+  # variables.
+  # TODO(ehmaldonado): Remove this once the bug in gclient is fixed.
+  'checkout_android': False,
+
   # Pull in Android native toolchain dependencies for Chrome OS too, so we can
   # build ARC++ support libraries.
   'checkout_android_native_support': 'checkout_android or checkout_chromeos',
@@ -2056,7 +2061,7 @@ hooks = [
     # Note: On Win, this should run after win_toolchain, as it may use it.
     'name': 'clang',
     'pattern': '.',
-    'action': ['python', 'src/tools/clang/scripts/update.py'],
+    'action': ['python', 'src/tools/clang/scripts/update.py', '--with-android={checkout_android}'],
   },
   {
     # This is supposed to support the same set of platforms as 'clang' above.

tools/clang/scripts/update.py

@@ -895,6 +895,15 @@ def UpdateClang(args):
   return 0
 
 
+def gn_arg(v):
+  if v == 'True':
+    return True
+  if v == 'False':
+    return False
+  raise argparse.ArgumentTypeError('Expected one of %r or %r' % (
+      'True', 'False'))
+
+
 def main():
   parser = argparse.ArgumentParser(description='Build Clang.')
   parser.add_argument('--bootstrap', action='store_true',
@@ -929,10 +938,12 @@ def main():
                       'and using prebuilt cmake binaries')
   parser.add_argument('--verify-version',
                       help='verify that clang has the passed-in version')
+  parser.add_argument('--with-android', type=gn_arg, nargs='?', const=True,
+                      help='build the Android ASan runtime (linux only)',
+                      default=sys.platform.startswith('linux'))
   parser.add_argument('--without-android', action='store_false',
                       help='don\'t build Android ASan runtime (linux only)',
-                      dest='with_android',
-                      default=sys.platform.startswith('linux'))
+                      dest='with_android')
   parser.add_argument('--without-fuchsia', action='store_false',
                       help='don\'t build Fuchsia clang_rt runtime (linux/mac)',
                       dest='with_fuchsia',
@@ -986,9 +997,6 @@ def main():
     PACKAGE_VERSION = CLANG_REVISION + '-0'
 
     args.force_local_build = True
-    if 'OS=android' not in os.environ.get('GYP_DEFINES', ''):
-      # Only build the Android ASan rt on ToT bots when targetting Android.
-      args.with_android = False
     # Don't build fuchsia runtime on ToT bots at all.
     args.with_fuchsia = False