Need to access tabIndex in CyclopsEditor, made it protected

It was in the private section. Still is practically...
Motivation:
Whenever an editor is closed, it destroy it's DataViewport tab (if it exists)
I don't want my "shared" tab to be closed when any one editor is closed, and I can fool the
VisualizerEditor destructor now.

Source/Processors/Editors/VisualizerEditor.h

@@ -196,10 +196,10 @@ protected: // these should be available to sub-classes if needed.
     // So that we can override buttonClick. That's not possible if these are private.
     SelectorButton* windowSelector;
     SelectorButton* tabSelector;
+    int tabIndex;
 
 private:
     void initializeSelectors();
-    int tabIndex;
 
     JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(VisualizerEditor);