Add a base class of Texture for interfacing with the mailbox manager.

gpu/command_buffer/service/mailbox_manager_impl.h

Index: gpu/command_buffer/service/mailbox_manager_impl.h
diff --git a/gpu/command_buffer/service/mailbox_manager_impl.h b/gpu/command_buffer/service/mailbox_manager_impl.h
index b903459b75b62546a990c537bcaf95474d4da5fe..e44ac046dbd67e80cd493f2e7548292871c5f64c 100644
--- a/gpu/command_buffer/service/mailbox_manager_impl.h
+++ b/gpu/command_buffer/service/mailbox_manager_impl.h
@@ -18,7 +18,7 @@
 namespace gpu {
 namespace gles2 {
 
-class Texture;
+class TextureBase;
 class TextureManager;
 
 // Manages resources scoped beyond the context or context group level.
@@ -27,12 +27,12 @@ class GPU_EXPORT MailboxManagerImpl : public MailboxManager {
   MailboxManagerImpl();
 
   // MailboxManager implementation:
-  Texture* ConsumeTexture(const Mailbox& mailbox) override;
-  void ProduceTexture(const Mailbox& mailbox, Texture* texture) override;
+  TextureBase* ConsumeTexture(const Mailbox& mailbox) override;
+  void ProduceTexture(const Mailbox& mailbox, TextureBase* texture) override;
   bool UsesSync() override;
   void PushTextureUpdates(const SyncToken& token) override {}
   void PullTextureUpdates(const SyncToken& token) override {}
-  void TextureDeleted(Texture* texture) override;
+  void TextureDeleted(TextureBase* texture) override;
 
  protected:
   ~MailboxManagerImpl() override;
@@ -40,13 +40,13 @@ class GPU_EXPORT MailboxManagerImpl : public MailboxManager {
  private:
   friend class base::RefCounted<MailboxManager>;
 
-  void InsertTexture(const Mailbox& mailbox, Texture* texture);
+  void InsertTexture(const Mailbox& mailbox, TextureBase* texture);
 
   // This is a bidirectional map between mailbox and textures. We can have
   // multiple mailboxes per texture, but one texture per mailbox. We keep an
   // iterator in the MailboxToTextureMap to be able to manage changes to
   // the TextureToMailboxMap efficiently.
-  typedef std::multimap<Texture*, Mailbox> TextureToMailboxMap;
+  typedef std::multimap<TextureBase*, Mailbox> TextureToMailboxMap;
   typedef std::map<Mailbox, TextureToMailboxMap::iterator>
       MailboxToTextureMap;