[Cronet] add base proguard flags

components/cronet/tools/generate_proguard_file.py

Index: components/cronet/tools/generate_proguard_file.py
diff --git a/components/cronet/tools/generate_proguard_file.py b/components/cronet/tools/generate_proguard_file.py
new file mode 100755
index 0000000000000000000000000000000000000000..5696caa97a2a4ed1d1f3fce88be796e1a550ec4e
--- /dev/null
+++ b/components/cronet/tools/generate_proguard_file.py
@@ -0,0 +1,32 @@
+#!/usr/bin/env python
+#
+# Copyright 2016 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.
+
+import optparse
+import sys
+
+# Combines files in |input_files| as one proguard file and write that to
+# |output_file|
+def GenerateProguardFile(output_file, input_files):
+  try:
+    with open(output_file, "wb") as target:
+      for input_file in input_files:
+        with open(input_file, "rb") as current:
+          target.write(current.read())

[mef, 2016/08/10 01:25:35]

what would happen if there is no newline at the end of one of the input files?

[xunjieli, 2016/08/11 21:05:53]

Done. You are right. That will be bad. I changed it so we append line by line.

+  except IOError:
+    raise Exception("Proguard file generation failed")
+
+
+def main():
+  parser = optparse.OptionParser()
+  parser.add_option('--output-file',
+          help='Output file for the generated proguard file')
+
+  options, input_files = parser.parse_args()
+  GenerateProguardFile(options.output_file, input_files)
+
+
+if __name__ == '__main__':
+  sys.exit(main())