[Mac/GN] Allow the info_plist template caller to specify the plist format.

build/config/mac/rules.gni

 # Copyright 2015 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("//build/config/mac/base_rules.gni")
 
 # Generates Info.plist files for Mac apps and frameworks.
 #
 # Arguments
 #
 #     info_plist:
 #         string, the path to an plist file that will be included in the final
 #         Info.plist generated.
 #
 #     executable_name:
 #         string, name of the generated target used for the product
 #         and executable name as specified in the output Info.plist.
 #
 #     extra_substitutions:
 #         (optional) string array, 'key=value' pairs for extra fields which are
 #         specified in a source Info.plist template.
 template("mac_info_plist") {
   info_plist(target_name) {
+    format = "xml1"
     extra_substitutions = []
     if (defined(invoker.extra_substitutions)) {
       extra_substitutions = invoker.extra_substitutions
     }
     extra_substitutions += [
       "MAC_SDK_BUILD=$mac_sdk_build",
       "MAC_SDK_NAME=$mac_sdk_name$mac_sdk_version",
     ]
     plist_templates = [
       "//build/config/mac/BuildInfo.plist",
@@ skipping 267 matching lines @@
                            ])
     if (!defined(deps)) {
       deps = []
     }
     deps += [ ":$_loadable_module_bundle_data" ]
 
     bundle_root_dir = "$root_out_dir/$_output_name.plugin/Contents"
     bundle_executable_dir = "$bundle_root_dir/MacOS"
   }
 }