Stub in Mac viewer code.

tools/viewer/sk_app/mac/GLWindowContext_mac.h

 
 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
-#ifndef GLWindowContext_unix_DEFINED
-#define GLWindowContext_unix_DEFINED
+#ifndef GLWindowContext_mac_DEFINED
+#define GLWindowContext_mac_DEFINED
 
 #include "../GLWindowContext.h"
-#include "Window_unix.h"
+#include "Window_mac.h"
 
 namespace sk_app {
 
-class GLWindowContext_unix : public GLWindowContext {
+class GLWindowContext_mac : public GLWindowContext {
 public:
     friend GLWindowContext* GLWindowContext::Create(void* platformData, const DisplayParams&);
 
-    ~GLWindowContext_unix() override;
+    ~GLWindowContext_mac() override;
 
     void onSwapBuffers() override;
 
     void onInitializeContext(void*, const DisplayParams&) override;
     void onDestroyContext() override;
 
 private:
-    GLWindowContext_unix(void*, const DisplayParams&);
+    GLWindowContext_mac(void*, const DisplayParams&);
 
+#if 0
+    // TODO: add Mac-specific GL display objects
     Display*     fDisplay;
     XWindow      fWindow;
     XVisualInfo* fVisualInfo;
     GLXContext   fGLContext;
+#endif
 };
 
 
 }
 
 #endif