Mojo Bindings: Put typemap files in the build dependency tree

mojo/public/tools/bindings/chromium_bindings_configuration.gni

 # 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.
 
 _typemap_imports = [
   "//ash/public/interfaces/typemaps.gni",
   "//cc/ipc/typemaps.gni",
   "//chrome/browser/media/router/mojo/typemaps.gni",
   "//chrome/common/extensions/typemaps.gni",
   "//chrome/common/importer/typemaps.gni",
@@ skipping 38 matching lines @@
 foreach(typemap_import, _typemap_imports) {
   # Avoid reassignment error by assigning to empty scope first.
   _imported = {
   }
   _imported = read_file(typemap_import, "scope")
   _typemaps += _imported.typemaps
 }
 
 typemaps = []
 foreach(typemap, _typemaps) {
-  typemaps += [ read_file(typemap, "scope") ]
+  typemaps += [ {
+        filename = typemap
+        config = read_file(typemap, "scope")
+      } ]
 }
 
 _typemaps_mac = []
 foreach(typemap_import, _typemap_imports_mac) {
   _imported = {
   }
   _imported = read_file(typemap_import, "scope")
   _typemaps_mac += _imported.typemaps
 }
 
 typemaps_mac = []
 foreach(typemap, _typemaps_mac) {
-  typemaps_mac += [ read_file(typemap, "scope") ]
+  typemaps_mac += [ {
+        filename = typemap
+        config = read_file(typemap, "scope")
+      } ]
 }