Add Windows, Mac, Android support to low bandwidth audio test

tools-webrtc/download_tools.py

Index: tools-webrtc/download_tools.py
diff --git a/tools-webrtc/download_tools.py b/tools-webrtc/download_tools.py
index dc64ebf8b80577b6facbe9031954d0c8d25ad3ef..123fd3a4a563583b08e30481f7c490145923a3f4 100755
--- a/tools-webrtc/download_tools.py
+++ b/tools-webrtc/download_tools.py
@@ -20,6 +20,8 @@ import sys
 
 
 SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
+# Needed to properly resolve PATH and executable extensions on Windows.

[kjellander_webrtc, 2017/03/27 09:05:10]

Skip the "and executable extensions" part in this script, since it's not used.

[oprypin_webrtc, 2017/03/27 09:19:07]

I think it is actually still relevant to resolve the extension for
download_from_google_storage.bat - I read somewhere that only .exe are resolved
automatically but can't find that reference anymore.

[kjellander_webrtc, 2017/03/27 09:46:51]

Ah, I see now. I somehow confused this in my head with that you would append
extensions, but you're talking about using the shell to auto-resolve extensions.
I'm sure windows cmd.exe auto-resolves .bat, so yes let's  keep this as is.

+USE_SHELL = sys.platform == 'win32'
 
 
 def main(directories):
@@ -37,7 +39,7 @@ def main(directories):
       path,
     ]
     print 'Downloading precompiled tools...'
-    subprocess.check_call(cmd)
+    subprocess.check_call(cmd, shell=USE_SHELL)
 
 
 if __name__ == '__main__':