Remove redundant color dispose calls and duplicate dark styling

Author: vogella

bundles/org.eclipse.ui.ide.application/src/org/eclipse/ui/internal/ide/application/IDEApplication.java

@@ -606,11 +606,7 @@ protected Shell getParentShell() {
 
 			@Override
 			protected Control createContents(Composite parent) {
-				Control contents = super.createContents(parent);
-				if (isDark) {
-					applyDarkStyles(getShell());
-				}
-				return contents;
+				return super.createContents(parent);
 			}
 		}.prompt(force);
 	}
@@ -934,10 +930,6 @@ private void applyDarkStyles(Shell shell) {
 		shell.setBackground(bg);
 		shell.setForeground(fg);
 		applyStylesRecursive(shell, bg, fg, linkColor);
-		shell.addDisposeListener(e -> {
-			bg.dispose();
-			fg.dispose();
-		});
 	}
 
 	private void applyStylesRecursive(Control control, Color bg, Color fg, Color linkColor) {