[mojo] Use base::Pickle for Message storage.

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.
 
 source_set("bindings") {
   sources = [
     "array.h",
     "associated_binding.h",
     "associated_group.h",
     "associated_interface_ptr.h",
@@ skipping 35 matching lines @@
     "lib/message.cc",
     "lib/message_builder.cc",
     "lib/message_builder.h",
     "lib/message_filter.cc",
     "lib/message_header_validator.cc",
     "lib/message_header_validator.h",
     "lib/message_internal.h",
     "lib/multiplex_router.cc",
     "lib/multiplex_router.h",
     "lib/no_interface.cc",
+    "lib/pickle_buffer.cc",
+    "lib/pickle_buffer.h",
     "lib/pipe_control_message_handler.cc",
     "lib/pipe_control_message_handler.h",
     "lib/pipe_control_message_handler_delegate.h",
     "lib/pipe_control_message_proxy.cc",
     "lib/pipe_control_message_proxy.h",
     "lib/router.cc",
     "lib/router.h",
     "lib/scoped_interface_endpoint_handle.cc",
     "lib/scoped_interface_endpoint_handle.h",
     "lib/string_serialization.cc",
@@ skipping 10 matching lines @@
     "message_filter.h",
     "no_interface.h",
     "string.h",
     "strong_binding.h",
     "struct_ptr.h",
     "type_converter.h",
   ]
 
   public_deps = [
     ":callback",
+    "//base",
     "//mojo/public/cpp/system",
   ]
 
   deps = [
     "//base",
     "//mojo/public/cpp/environment",
     "//mojo/public/interfaces/bindings:bindings_cpp_sources",
   ]
 }
 
 source_set("callback") {
   sources = [
     "callback.h",
     "lib/callback_internal.h",
     "lib/shared_data.h",
     "lib/shared_ptr.h",
     "lib/template_util.h",
   ]
 
   deps = [
     "//base",
     "//mojo/public/cpp/system",
   ]
 }