map.dragPan still allows dragging the pan on mobile

mapbox-gl-js version: 1.6.1

browser: any mobile browser (tested: edge, chrome, firefox, dolphin)

Steps to Trigger Behavior

1. Two fingers on a touch screen
2. And drag the camera

Link to Demonstration

this.map = new mapboxgl.Map({
    container: 'game_map',
    style: 'mapbox://styles/mapbox/light-v10',
    center: [location.coords.longitude, location.coords.latitude],
    zoom: 20,
    touchZoomRotate: {around: 'center'},
    scrollZoom: {around: 'center'},
    pitch: 60,
    bearing: -60,
    antialias: true,
    attributionControl: false,
    dragPan: false,
    maxZoom: 22,
    minZoom: 17
});

Expected Behavior

When the user tries to drag the pan with two fingers the pan should not move, the user is only allowed to rotate the camera (not move it).

Actual Behavior

When the user tries to drag the pan with two fingers the pan moves with the touch input from the user.

Start by reproducing the demonstrated Map configuration on a mobile browser with dragPan disabled, using a two-finger drag. Then trace the touch gesture handling for map panning and rotation. Done means two fingers can rotate the camera without moving its pan position when dragPan is false.