Upgrade Tex{Sub}Image{2|3}D to handle ES3 unpack parameters.

gpu/command_buffer/client/gles2_implementation.h

Index: gpu/command_buffer/client/gles2_implementation.h
diff --git a/gpu/command_buffer/client/gles2_implementation.h b/gpu/command_buffer/client/gles2_implementation.h
index 8b8ef63fdc95234e32e1bb803a4f1c3a11083b70..02314d07fd644f1f20f59d3d2e59fd0be10bb4a4 100644
--- a/gpu/command_buffer/client/gles2_implementation.h
+++ b/gpu/command_buffer/client/gles2_implementation.h
@@ -297,6 +297,12 @@ class GLES2_IMPL_EXPORT GLES2Implementation
       kUnknownExtensionStatus
   };
 
+  enum Dimension {
+      k2D,
+      k3D,
+  };
+
+
   // Base class for mapped resources.
   struct MappedResource {
     MappedResource(GLenum _access, int _shm_id, void* mem, unsigned int offset)
@@ -693,6 +699,8 @@ class GLES2_IMPL_EXPORT GLES2Implementation
   void UpdateCachedExtensionsIfNeeded();
   void InvalidateCachedExtensions();
 
+  PixelStoreParams GetUnpackParameters(Dimension dimension);
+
   GLES2Util util_;
   GLES2CmdHelper* helper_;
   TransferBufferInterface* transfer_buffer_;