Bug 36672 call hierarchy: Should show a progress bar
The Call Hierarchy view should show a progress bar when searching for callers/callees, allowing the user to abort the search.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/callhierarchy/CallHierarchyViewPart.java
ISelectionChangedListener {
    private CallHierarchyViewSiteAdapter fViewSiteAdapter;
    private CallHierarchyViewAdapter fViewAdapter;
    private static final String DIALOGSTORE_VIEWORIENTATION = "CallHierarchyViewPart.orientation"; 
    private static final String DIALOGSTORE_CALL_MODE = "CallHierarchyViewPart.call_mode"; 
    private static final String TAG_ORIENTATION = "orientation"; 
    private static final String TAG_CALL_MODE = "call_mode"; 
    private static final String TAG_IMPLEMENTORS_MODE = "implementors_mode"; 
    private static final String TAG_RATIO = "ratio"; 
    static final int VIEW_ORIENTATION_VERTICAL = 0;
    static final int VIEW_ORIENTATION_HORIZONTAL = 1;
    static final int VIEW_ORIENTATION_SINGLE = 2;
    static final int CALL_MODE_CALLERS = 0;
    static final int CALL_MODE_CALLEES = 1;
    static final int IMPLEMENTORS_ENABLED = 0;
    static final int IMPLEMENTORS_DISABLED = 1;
    static final String GROUP_SEARCH_SCOPE = "MENU_SEARCH_SCOPE"; 
	static final String ID_CALL_HIERARCHY = "org.eclipse.jdt.callhierarchy.view";