[Aura] Added Support for rendering software compositor frames as cc::TextureLayers.

cc/resources/texture_mailbox.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 CC_RESOURCES_TEXTURE_MAILBOX_H_
 #define CC_RESOURCES_TEXTURE_MAILBOX_H_
 
 #include <string>
 
-#include "base/basictypes.h"
 #include "base/callback.h"
+#include "base/memory/shared_memory.h"
 #include "cc/base/cc_export.h"
 #include "gpu/command_buffer/common/mailbox.h"
+#include "ui/gfx/size.h"
 
 namespace cc {
 
+// TODO(skaslev, danakj) Rename this class more apropriately since now it
+// can hold a shared memory resource as well as a texture mailbox.
 class CC_EXPORT TextureMailbox {
  public:
   typedef base::Callback<void(unsigned sync_point,
                               bool lost_resource)> ReleaseCallback;
   TextureMailbox();
   TextureMailbox(const std::string& mailbox_name,
                  const ReleaseCallback& callback);
   TextureMailbox(const gpu::Mailbox& mailbox_name,
                  const ReleaseCallback& callback);
   TextureMailbox(const gpu::Mailbox& mailbox_name,
                  const ReleaseCallback& callback,
                  unsigned sync_point);
   TextureMailbox(const gpu::Mailbox& mailbox_name,
                  const ReleaseCallback& callback,
                  unsigned texture_target,
                  unsigned sync_point);
+  TextureMailbox(base::SharedMemory* shared_memory,
+                 gfx::Size size,

[danakj, 2013/06/07 14:56:42]

I feel like including the size inside the TextureMailbox is going to be awkward.

When I want to give you a texture mailbox, if it contains a texture, I'll have
to pass a size along with it. If it contains a shared memory, then I don't. But
I'll still have a size parameter there to handle the texture case, it's just
unused?

Like HereIsATextureMailbox(TextureMailbox& mailbox, gfx::Size
size_if_mailbox_is_a_texture). That's pretty awkward. Since the hardware path
needs a size passed along with it, would it make sense to remove the size from
here for the shared memory case and require it to be passed separately as well?

[slavi, 2013/06/07 21:49:21]

We talked this over offline.

+                 const ReleaseCallback& callback);
 
   ~TextureMailbox();
 
+  bool IsValid() const { return IsTexture() || IsSharedMemory(); }
+  bool IsTexture() const { return !name_.IsZero(); }
+  bool IsSharedMemory() const { return shared_memory_ != NULL; }
+
+  bool Equals(const TextureMailbox&) const;
+  bool ContainsMailbox(const gpu::Mailbox&) const;
+  bool ContainsHandle(base::SharedMemoryHandle handle) const;
+
   const ReleaseCallback& callback() const { return callback_; }
   const int8* data() const { return name_.name; }
-  bool Equals(const gpu::Mailbox&) const;
-  bool Equals(const TextureMailbox&) const;
-  bool IsEmpty() const;
   const gpu::Mailbox& name() const { return name_; }
   void ResetSyncPoint() { sync_point_ = 0; }
   void RunReleaseCallback(unsigned sync_point, bool lost_resource) const;
   void SetName(const gpu::Mailbox&);
   unsigned target() const { return target_; }
   unsigned sync_point() const { return sync_point_; }
 
+  base::SharedMemory* shared_memory() const { return shared_memory_; }
+  gfx::Size shared_memory_size() const { return shared_memory_size_; }
+  size_t shared_memory_size_in_bytes() const;
+
+  TextureMailbox CopyWithNewCallback(const ReleaseCallback& callback) const;
+
  private:
   gpu::Mailbox name_;
   ReleaseCallback callback_;
   unsigned target_;
   unsigned sync_point_;
+  base::SharedMemory* shared_memory_;
+  gfx::Size shared_memory_size_;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_TEXTURE_MAILBOX_H_