Replacing allocate bitmap IPC messages with a new Mojo interface.

content/common/shared_memory_allocator.mojom

Index: content/common/shared_memory_allocator.mojom
diff --git a/content/common/shared_memory_allocator.mojom b/content/common/shared_memory_allocator.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..ffa20ab61eaae2ed8bbc63eaf35b18775d3ec88f
--- /dev/null
+++ b/content/common/shared_memory_allocator.mojom
@@ -0,0 +1,16 @@
+// 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.
+
+module content.mojom;
+
+import "gpu/ipc/common/mailbox.mojom";
+
+// MemoryAllocator lives in the browser process and .
+interface SharedMemoryAllocator {
+
+
+  AllocatedSharedBitmap(handle<shared_buffer> buffer, gpu.mojom.Mailbox id);
+
+  DeletedSharedBitmap(gpu.mojom.Mailbox id);
+};