Add support for Mac/iOS application bundles to GN tool.

tools/gn/function_forward_variables_from.cc

 // 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.
 
 #include "tools/gn/err.h"
 #include "tools/gn/functions.h"
 #include "tools/gn/parse_tree.h"
 #include "tools/gn/scope.h"
 
 namespace functions {
@@ skipping 115 matching lines @@
     "  }\n"
     "\n"
     "  # This is a template around either a target whose type depends on a\n"
     "  # global variable. It forwards all values from the invoker.\n"
     "  template(\"my_wrapper\") {\n"
     "    target(my_wrapper_target_type, target_name) {\n"
     "      forward_variables_from(invoker, \"*\")\n"
     "    }\n"
     "  }\n"
     "\n"
-    "  # A template that wraps another. It adds behavior based on one \n"
+    "  # A template that wraps another. It adds behavior based on one\n"
     "  # variable, and forwards all others to the nested target.\n"
     "  template(\"my_ios_test_app\") {\n"
     "    ios_test_app(target_name) {\n"
     "      forward_variables_from(invoker, \"*\", [\"test_bundle_name\"])\n"
     "      if (!defined(extra_substitutions)) {\n"
     "        extra_substitutions = []\n"
     "      }\n"
     "      extra_substitutions += [ \"BUNDLE_ID_TEST_NAME=$test_bundle_name\" "
                                                                           "]\n"
     "    }\n"
@@ skipping 71 matching lines @@
     }
   }
 
   // Not the right type of argument.
   *err = Err(what_value, "Not a valid list of variables to copy.",
              "Expecting either the string \"*\" or a list of strings.");
   return Value();
 }
 
 }  // namespace functions