Bug 23459 add preference option to turn off variable guessing on method completion
request from Adam
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/JavaEditorPreferencePage.java
new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, CompilationUnitEditor.CURRENT_LINE),
		
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, CompilationUnitEditor.PRINT_MARGIN_COLOR),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.INT, CompilationUnitEditor.PRINT_MARGIN_COLUMN),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, CompilationUnitEditor.PRINT_MARGIN),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, AbstractTextEditor.PREFERENCE_COLOR_FIND_SCOPE),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, CompilationUnitEditor.LINKED_POSITION_COLOR),
		
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, CompilationUnitEditor.PROBLEM_INDICATION_COLOR),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, CompilationUnitEditor.PROBLEM_INDICATION),
		
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, JavaEditorPreferencePage.PREF_SHOW_TEMP_PROBLEMS),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, JavaEditorPreferencePage.PREF_SYNC_OUTLINE_ON_CURSOR_MOVE),
		
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, CompilationUnitDocumentProvider.HANDLE_TEMPORARY_PROBLEMS),
		
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, CompilationUnitEditor.OVERVIEW_RULER),
		
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, JavaEditor.LINE_NUMBER_COLOR),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, JavaEditor.LINE_NUMBER_RULER),
				
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, CompilationUnitEditor.SPACES_FOR_TABS),
		
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, ContentAssistPreference.AUTOACTIVATION),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.INT, ContentAssistPreference.AUTOACTIVATION_DELAY),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.BOOLEAN, ContentAssistPreference.AUTOINSERT),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, ContentAssistPreference.PROPOSALS_BACKGROUND),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, ContentAssistPreference.PROPOSALS_FOREGROUND),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, ContentAssistPreference.PARAMETERS_BACKGROUND),
		new OverlayPreferenceStore.OverlayKey(OverlayPreferenceStore.STRING, ContentAssistPreference.PARAMETERS_FOREGROUND),