[mojo] Add pickling support for native-only structs

mojo/public/cpp/bindings/lib/bindings_internal.h

 // Copyright 2013 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.
 
 #ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDINGS_INTERNAL_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDINGS_INTERNAL_H_
 
 #include "mojo/public/cpp/bindings/lib/interface_id.h"
 #include "mojo/public/cpp/bindings/lib/template_util.h"
 #include "mojo/public/cpp/bindings/struct_ptr.h"
@@ skipping 19 matching lines @@
 };
 static_assert(sizeof(ArrayHeader) == 8, "Bad_sizeof(ArrayHeader)");
 
 template <typename T>
 union StructPointer {
   uint64_t offset;
   T* ptr;
 };
 static_assert(sizeof(StructPointer<char>) == 8, "Bad_sizeof(StructPointer)");
 
+union NativePointer {

[yzshen1, 2015/12/15 21:20:26]

Please define it as an alias of ArrayPointer<uint8_t>.

[Ken Rockot(use gerrit already), 2015/12/15 23:31:07]

Actually I've decided to just get rid of this altogether. Instead the generator
just emits an ArrayPointer<uint8_t>, and I've added code so that array
validation params for native-only fields basically match those of string
validation. WDYT?

+  uint64_t offset;
+  Array_Data<uint8_t>* ptr;
+};
+static_assert(sizeof(NativePointer) == 8, "Bad_sizeof(NativePointer)");
+
 template <typename T>
 union ArrayPointer {
   uint64_t offset;
   Array_Data<T>* ptr;
 };
 static_assert(sizeof(ArrayPointer<char>) == 8, "Bad_sizeof(ArrayPointer)");
 
 using StringPointer = ArrayPointer<char>;
 static_assert(sizeof(StringPointer) == 8, "Bad_sizeof(StringPointer)");
 
@@ skipping 73 matching lines @@
 };
 template <typename S>
 struct WrapperTraits<S, true> {
   typedef typename S::Data_* DataType;
 };
 
 }  // namespace internal
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDINGS_INTERNAL_H_