Bug 266699 [CommonNavigator] Remove CommonDropAdapter.setCurrentOperation
This has been replaced by overrideOperation() which does the same thing. Note that setCurrentOperation() was added in M5 so it's never really been API yet.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/navigator/CommonDropAdapter.java
if (Policy.DEBUG_DND) {
			System.out.println("CommonDropAdapter.validateDrop (begin) operation: " + theDropOperation + " target: " + aDropTarget + " transferType: " + theTransferData.type); 
			
		}
		boolean result = false;
		IStatus valid = null;
		if (super.validateDrop(aDropTarget, theDropOperation, theTransferData)) {
			result = true; 
			if (Policy.DEBUG_DND) {
				System.out
						.println("CommonDropAdapter.validateDrop valid for plugin transfer"); 
			}
		} else {
			Object target = aDropTarget != null ? aDropTarget : getViewer().getInput();
			if (Policy.DEBUG_DND) { 
				System.out.println("CommonDropAdapter.validateDrop target: " + target); 
				System.out.println("CommonDropAdapter.validateDrop local selection: " + 
						LocalSelectionTransfer.getTransfer().getSelection());
			}
			CommonDropAdapterAssistant[] assistants = dndService
					.findCommonDropAdapterAssistants(target,
							theTransferData);
			for (int i = 0; i < assistants.length; i++) {
				if (Policy.DEBUG_DND) { 
					System.out
							.println("CommonDropAdapter.validateDrop checking assistant: \""+assistants[i]); 
				}					
				try { 
					assistants[i].setCurrentEvent(getCurrentEvent());
					valid = assistants[i].validateDrop(target,