correctly delete glbuffers

libraries/gpu/src/gpu/Context.h

@@ -11,6 +11,7 @@
 #ifndef hifi_gpu_Context_h
 #define hifi_gpu_Context_h
 
+#include <QDebug>
 #include <assert.h>
 
 #include "Resource.h"
@@ -21,7 +22,7 @@ namespace gpu {
 class GPUObject {
 public:
     GPUObject() {}
-    ~GPUObject() {}
+    virtual ~GPUObject() {}
 };
 
 class Batch;

libraries/gpu/src/gpu/GLBackend.h

@@ -32,7 +32,7 @@ public:
     static void checkGLError();
 
 
-    class GLBuffer {
+    class GLBuffer : public GPUObject {
     public:
         Stamp _stamp;
         GLuint _buffer;