[dropEnabled]=false still accept the draggable object on iPad

[Vanchan]

Please remove sections that are not required.

• I'm submitting a ...
  [x ] bug report
  [ ] feature request
  [ ] other

• What is the current behavior?
  [dropEnabled] is not working on iPad. (Works perfectly fine on web)
  Even if it set to false the droppable zone always accept the draggable object.

The [dragHintClass] & [dragOverClass] will not work as expected but once you drop the draggable into the droppable zone it will accept the draggable object.

• If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem via https://plnkr.co or similar.

Set the [dropEnabled]=false.
Enter developer mode.
Select iPad.
Drag the draggable to the droppable zone.

dragHintClass and dragOverClass won't work but the droppable zone will accept the draggable object.

• What is the expected behavior?

The droppable zone with [dropEnabled] attribute set to false should not accept the draggable object.

• Please tell us about your environment:

• Ionic version: 3.18.0
• Angular version: 5.0.1
• Angular CLI Version: 1.5.3
• Browser: [Chrome Version 62.0.3202.94 (Official Build) (64-bit) ]