C bindings pt3: Type table definitions and barebones files to get generated code to compile.

mojo/public/c/bindings/array.h

+// 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.
+
+#ifndef MOJO_PUBLIC_C_BINDINGS_ARRAY_H_
+#define MOJO_PUBLIC_C_BINDINGS_ARRAY_H_
+
+#include <stdint.h>
+
+#include "mojo/public/c/system/macros.h"
+
+MOJO_BEGIN_EXTERN_C
+
+// The fields below are just the header of a mojom array. The bytes that
+// immediately follow this struct consist of |num_bytes -
+// sizeof(MojomArrayHeader)| bytes describing |num_elements| elements of the
+// array.
+struct MojomArrayHeader {
+  // num_bytes includes the size of this struct along with the
+  // accompanying array bytes that follow these fields.
+  uint32_t num_bytes;
+  uint32_t num_elements;
+};
+MOJO_STATIC_ASSERT(sizeof(struct MojomArrayHeader) == 8,
+                   "struct MojomArrayHeader must be 8 bytes.");
+
+// This union is used to represent references to a mojom array.
+union MojomArrayHeaderPtr {
+  // |ptr| is used to access the array when it hasn't been encoded yet.
+  struct MojomArrayHeader* ptr;
+  // |offset| is used to access the array after it has been encoded.
+  uint64_t offset;
+};
+MOJO_STATIC_ASSERT(sizeof(union MojomArrayHeaderPtr) == 8,
+                   "union MojomArrayHeaderPtr must be 8 bytes.");
+
+MOJO_END_EXTERN_C
+
+#endif  // MOJO_PUBLIC_C_BINDINGS_ARRAY_H_