Strip comments and whitespace from javascript resources

tools/grit/grit/format/minifier.py

+# 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.
+"""Framework for stripping whitespace and comments from resource files"""
+
+import subprocess
+
+__js_minifier = None
+
+
+def SetJsMinifier(minifier):
+  global __js_minifier
+  __js_minifier = minifier.split()
+
+
+def Minify(source, file_type):
+  if not file_type == '.js' or not __js_minifier:
+    return source
+  p = subprocess.Popen(
+      __js_minifier,
+      stdin=subprocess.PIPE,
+      stdout=subprocess.PIPE,
+      stderr=subprocess.PIPE)
+  (stdout, stderr) = p.communicate(source)
+  if stderr:
+    print stderr
+  if p.returncode != 0:
+    print 'Minification failed, using original source'
+    return source
+  return stdout