Bug 139483 IDEIdleHelper should be a system job
RC2 The IDEIdleHelper is not a system job so you periodically get a "Collecting garbage" job showing up in the ProgressView.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/IDEIdleHelper.java
public void handleEvent(Event event) {
				display.timerExec(IDLE_INTERVAL, handler);
			}
		};
		display.addFilter(SWT.KeyUp, idleListener);
		display.addFilter(SWT.MouseUp, idleListener);
	}
	/**
	 * Shuts down the idle helper, removing any installed listeners, etc.
	 */
	void shutdown() {
		if (idleListener == null) {
			return;
		}
		final Display display = configurer.getWorkbench().getDisplay();
		if (display != null && !display.isDisposed()) {
			try {
				display.asyncExec(new Runnable() {
					public void run() {
						display.timerExec(-1, handler);
						display.removeFilter(SWT.KeyUp, idleListener);
						display.removeFilter(SWT.MouseUp, idleListener);
					}
				});
			} catch (SWTException ex) {
				
			}			
		}
	}
}