Review comment: Add messages to AssertionHelper methods.
nit: final keyword in UITest.
Add BaseHelper class.
Add page name when waiting for page index in AboutHomeComponent.
Move GestureHelper to BaseHelper.
Move AssertionHelper to BaseHelper.
Move CommonUseHelper to BaseHelper.
Move DeviceHelper to BaseHelper.
Move ViewHelper to BaseHelper.
Add Components to BaseHelper.
Move WaitHelper to BaseHelper.
Move GeckoHelper to BaseHelper.