Bug 22380 "No Source" class file editor does not fetch keyboard focus
Build N20020813 Test Case: 1. From the package explorer open a class from a JAR without attached source 2. Activate the editor 3. Select something in another view (note: selection is blue) 4. Activate the class file editor by clicking on the tab ==> selection in other view remains blue but should be gray. Suggest to set the keyboard focus to the "Attach Source..." button
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/ClassFileEditor.java
fBackgroundColor= display.getSystemColor(SWT.COLOR_LIST_BACKGROUND);
				fForegroundColor= display.getSystemColor(SWT.COLOR_LIST_FOREGROUND);
				fSeparatorColor= new Color(display, 152, 170, 203);
		
				JFaceResources.getFontRegistry().addListener(this);
		
				fScrolledComposite= new ScrolledComposite(parent, SWT.H_SCROLL | SWT.V_SCROLL);
				fScrolledComposite.setAlwaysShowScrollBars(false);
				fScrolledComposite.setExpandHorizontal(true);
				fScrolledComposite.setExpandVertical(true);
				fScrolledComposite.addDisposeListener(new DisposeListener() {
					public void widgetDisposed(DisposeEvent e) {
						JFaceResources.getFontRegistry().removeListener(SourceAttachmentForm.this);
						fScrolledComposite= null;
						fSeparatorColor.dispose();
						fSeparatorColor= null;				
						fBannerLabels.clear();
						fHeaderLabels.clear();
						if (fFont != null) {
							fFont.dispose();
							fFont= null;
						}
					}
				});
				
				fScrolledComposite.addControlListener(new ControlListener() {
					public void controlMoved(ControlEvent e) {}
					public void controlResized(ControlEvent e) {
						Rectangle clientArea = fScrolledComposite.getClientArea();