Add support for extra GN args to Android build script.

tools-webrtc/android/build_aar.py

Index: tools-webrtc/android/build_aar.py
diff --git a/tools-webrtc/android/build_aar.py b/tools-webrtc/android/build_aar.py
index 7f6937f2001fa54d2bcae0ea5fd7d61557fb6841..d58f9dd330b053e2b959a81ffdcb758282723a05 100755
--- a/tools-webrtc/android/build_aar.py
+++ b/tools-webrtc/android/build_aar.py
@@ -54,6 +54,8 @@ def _ParseArgs():
       help='Use goma.')
   parser.add_argument('--verbose', action='store_true', default=False,
       help='Debug logging.')
+  parser.add_argument('--extra-gn-args', action='append', default=[],

[sakal, 2017/02/06 09:24:11]

I would prefer this be a regular string parameter. You can pass multiple
parameters:
--extra-gn-args='is_debug=false is_component_build=true'

[kjellander_webrtc, 2017/02/06 14:44:12]

Since I have action='append' it is possible to pass multiple arguments by
specifying the same flag multiple times, like --extra-gn-args=foo=\"bar\"
--extra-gn-args='baz=\"wee\"
I think that's better than string.
I tried passing two flags as a string and it actually also works:
--extra-gn-args='goma_dir="/usr/local/google/home/kjellander/goma" foo="bar"'

See https://docs.python.org/2.7/library/argparse.html#action for more info.

[sakal, 2017/02/06 14:52:57]

I find passing arguments one by one a little cumbersome but if you prefer it ok.

+      help='Additional GN args to be used during Ninja generation.')
   return parser.parse_args()
 
 
@@ -108,7 +110,7 @@ def _GetArmVersion(arch):
     raise Exception('Unknown arch: ' + arch)
 
 
-def Build(tmp_dir, arch, use_goma):
+def Build(tmp_dir, arch, use_goma, extra_gn_args):
   """Generates target architecture using GN and builds it using ninja."""
   logging.info('Building: %s', arch)
   output_directory = _GetOutputDirectory(tmp_dir, arch)
@@ -123,7 +125,7 @@ def Build(tmp_dir, arch, use_goma):
   if arm_version:
     gn_args['arm_version'] = arm_version
   gn_args_str = '--args=' + ' '.join([
-      k + '=' + _EncodeForGN(v) for k, v in gn_args.items()])
+      k + '=' + _EncodeForGN(v) for k, v in gn_args.items()] + extra_gn_args)

[sakal, 2017/02/06 09:24:11]

I would prefer a system where you can override existing args but if that is too
much work this is ok.

[kjellander_webrtc, 2017/02/06 14:44:12]

argparse doesn't support dicts, so I think it's a little too much work,
unfortunately.

[sakal, 2017/02/06 14:52:57]

Yeah, you would have to manually parse the list into a dictionary. Let's keep as
is then.

 
   _RunGN(['gen', output_directory, gn_args_str])
 
@@ -162,7 +164,7 @@ def main():
   tmp_dir = tempfile.mkdtemp()
 
   for arch in args.arch:
-    Build(tmp_dir, arch, args.use_goma)
+    Build(tmp_dir, arch, args.use_goma, args.extra_gn_args)
 
   with zipfile.ZipFile(args.output, 'w') as aar_file:
     # Architecture doesn't matter here, arbitrarily using the first one.