Reduce size of mojo AssociatedBinding template expansions

mojo/public/cpp/bindings/BUILD.gn

 # 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.
 
 interfaces_bindings_gen_dir = "$root_gen_dir/mojo/public/interfaces/bindings"
 
 component("bindings") {
   sources = [
     # Normally, targets should depend on the source_sets generated by mojom
     # targets. However, the generated source_sets use portions of the bindings
     # library. In order to avoid linker warnings about locally-defined imports
     # in Windows components build, this target depends on the generated C++
     # files directly so that the EXPORT macro defintions match.
     "$interfaces_bindings_gen_dir/interface_control_messages.mojom-shared-internal.h",
     "$interfaces_bindings_gen_dir/interface_control_messages.mojom-shared.cc",
     "$interfaces_bindings_gen_dir/interface_control_messages.mojom-shared.h",
     "$interfaces_bindings_gen_dir/interface_control_messages.mojom.cc",
     "$interfaces_bindings_gen_dir/interface_control_messages.mojom.h",
     "$interfaces_bindings_gen_dir/pipe_control_messages.mojom-shared-internal.h",
     "$interfaces_bindings_gen_dir/pipe_control_messages.mojom-shared.cc",
     "$interfaces_bindings_gen_dir/pipe_control_messages.mojom-shared.h",
     "$interfaces_bindings_gen_dir/pipe_control_messages.mojom.cc",
     "$interfaces_bindings_gen_dir/pipe_control_messages.mojom.h",
     "array_data_view.h",
     "array_traits.h",
     "array_traits_carray.h",
     "array_traits_stl.h",
+    "associated_binding.cc",
     "associated_binding.h",
     "associated_binding_set.h",
     "associated_group.h",
     "associated_group_controller.h",
     "associated_interface_ptr.h",
     "associated_interface_ptr_info.h",
     "associated_interface_request.h",
     "binding.h",
     "binding_set.h",
     "bindings_export.h",
@@ skipping 139 matching lines @@
     ]
 
     public_deps = [
       ":bindings",
       "//third_party/WebKit/Source/wtf",
     ]
 
     public_configs = [ "//third_party/WebKit/Source:config" ]
   }
 }