Bug 31395 Child window of Preferences dialog centers between screens
On the Preferences->Java->Code Generation->Names tab, the Edit button opens a dialog that is split between multiple monitors, instead of centering on the main Preference window like the rest of its child windows do.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/OptionsConfigurationBlock.java
protected Shell getShell() {
		return fShell;
	}
	
	protected abstract Control createContents(Composite parent);
	
	protected void addCheckBox(Composite parent, String label, String key, String[] values, int indent) {
		ControlData data= new ControlData(key, values);
		
		GridData gd= new GridData(GridData.HORIZONTAL_ALIGN_FILL);
		gd.horizontalSpan= 2;
		gd.horizontalIndent= indent;
		
		Button checkBox= new Button(parent, SWT.CHECK);
		checkBox.setText(label);
		checkBox.setData(data);
		checkBox.setLayoutData(gd);
		checkBox.addSelectionListener(getSelectionListener());
		
		String currValue= (String)fWorkingValues.get(key);	
		checkBox.setSelection(data.getSelection(currValue) == 0);
		
		fCheckBoxes.add(checkBox);
	}
	
	protected void addComboBox(Composite parent, String label, String key, String[] values, String[] valueLabels, int indent) {
		ControlData data= new ControlData(key, values);
		
		GridData gd= new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING);
		gd.horizontalIndent= indent;