[Mac/GN] Move the bundle ID and creator code into the BRANDING file, and use it.

build/config/mac/rules.gni

Index: build/config/mac/rules.gni
diff --git a/build/config/mac/rules.gni b/build/config/mac/rules.gni
index 3c51905d42557e0516bdd08dc4dc8d7ce55cf703..224fd70b640c97600d023762c985373d5474122d 100644
--- a/build/config/mac/rules.gni
+++ b/build/config/mac/rules.gni
@@ -139,6 +139,10 @@ template("mac_xib_bundle_data") {
 #         structure will not be created, and build output will go directly
 #         into the framework subdirectory.
 #
+#     extra_substitutions:
+#         (optional) string array, 'key=value' pairs for extra fields which are
+#         specified in a source Info.plist template.
+#
 # See "gn help shared_library" for more information on arguments supported
 # by shared library target.
 template("mac_framework_bundle") {
@@ -154,9 +158,10 @@ template("mac_framework_bundle") {
     }
     forward_variables_from(invoker,
                            [
-                             "testonly",
+                             "extra_substitutions",
                              "info_plist",
                              "info_plist_target",
+                             "testonly",
                            ])
   }
 
@@ -203,6 +208,10 @@ template("mac_framework_bundle") {
 #     extra_configs:
 #         (optional) list of label, additional configs to apply to the
 #         executable target.
+#
+#     extra_substitutions:
+#         (optional) string array, 'key=value' pairs for extra fields which are
+#         specified in a source Info.plist template.
 template("mac_app_bundle") {
   _target_name = target_name
   _output_name = target_name
@@ -219,9 +228,10 @@ template("mac_app_bundle") {
     executable_name = _output_name
     forward_variables_from(invoker,
                            [
-                             "testonly",
+                             "extra_substitutions",
                              "info_plist",
                              "info_plist_target",
+                             "testonly",
                            ])
   }