Strip comments and whitespace from javascript resources

tools/grit/grit_rule.gni

 # Copyright 2014 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.
 
 # Instantiate grit. This will produce a script target to run grit, and a
 # static library that compiles the .cc files.
 #
 # Parameters
 #
 #   source (required)
@@ skipping 285 matching lines @@
 if (mac_views_browser) {
   grit_defines += [
     "-D",
     "mac_views_browser",
   ]
 }
 
 grit_resource_id_file = "//tools/gritsettings/resource_ids"
 grit_info_script = "//tools/grit/grit_info.py"
 
+js_minifier = rebase_path("//third_party/closure_compiler/js_minify.py")
+
 template("grit") {
   assert(defined(invoker.source),
          "\"source\" must be defined for the grit template $target_name")
 
   grit_inputs = [ invoker.source ]
 
   if (defined(invoker.resource_ids)) {
     resource_ids = invoker.resource_ids
   } else {
     resource_ids = grit_resource_id_file
@@ skipping 118 matching lines @@
       foreach(i, invoker.defines) {
         args += [
           "-D",
           i,
         ]
       }
     }
 
     args += grit_flags + assert_files_flags
 
+    if (strip_resource_files) {
+      args += [
+        "--js-minifier",
+        js_minifier,
+      ]
+    }
+
     if (defined(invoker.visibility)) {
       # This needs to include both what the invoker specified (since they
       # probably include generated headers from this target), as well as the
       # generated source set (since there's no guarantee that the visibility
       # specified by the invoker includes our target).
       #
       # Only define visibility at all if the invoker specified it. Otherwise,
       # we want to keep the public "no visibility specified" default.
       visibility = target_visibility + invoker.visibility
     }
@@ skipping 32 matching lines @@
     if (defined(invoker.configs)) {
       configs += invoker.configs
     }
 
     if (defined(invoker.visibility)) {
       visibility = invoker.visibility
     }
     output_name = grit_output_name
   }
 }