Avoid leaking render targets in debugger

debugger/QT/SkGLWidget.h

Index: debugger/QT/SkGLWidget.h
diff --git a/debugger/QT/SkGLWidget.h b/debugger/QT/SkGLWidget.h
index a8e4604fcabae69ba884dd926bbbafe8cef59ead..d78ff979facfd08226d5b29d98a5cb6e06cbe9f6 100644
--- a/debugger/QT/SkGLWidget.h
+++ b/debugger/QT/SkGLWidget.h
@@ -45,10 +45,11 @@ protected:
 
 
 private:
-    const GrGLInterface* fCurIntf;
-    GrContext* fCurContext;
-    SkGpuDevice* fGpuDevice;
-    SkCanvas* fCanvas;
+    void createRenderTarget();
+    SkAutoTUnref<const GrGLInterface> fCurIntf;
+    SkAutoTUnref<GrContext> fCurContext;
+    SkAutoTUnref<SkGpuDevice> fGpuDevice;
+    SkAutoTUnref<SkCanvas> fCanvas;
     SkDebugger* fDebugger;
     GrBackendRenderTargetDesc getDesc(int w, int h);
 };