Android StockBrowser 4.0.4 scroll jitter when dragging without lifting finger (regression) (fix supplied)

[borhub]

The change in #441 unfortunately degrades the drag-scrolling experience to the point of iScroll not being an acceptable solution to work around 4.0.4 Stock Browser's scrolling-div-related bugs for my team (e.g. on Galaxy S3 running the 4.0.4 Stock Browser).

A quick fix that enables both the transition cancellation, as well as smooth scrolling is to update the _transitionTime() method in the "isBadAndroid" section so that applies the non-zero transition time only when we're already in a transition that we need to cancel.

this.scrollerStyle[utils.style.transitionDuration] = this.isInTransition ? '0.001s' : '0s';

However, if we do only this, if the user then continues dragging (after tapping to cancel the transition) without lifting the finger, we still get the jitter. For that to go away, we need to do something like this

            this.scrollerStyle[utils.style.transitionDuration] = this.isInTransition ? '0.001s' : '0s';
            var that = this;
            setTimeout(function () {
                that.scrollerStyle[utils.style.transitionDuration] = '0s';
            }, 17);

Note this is very messy code potentially using the isInTransition property in a wrong way, not knowing implications, but it should illustrate a direction of a possible solution.

EDIT: we probably don't need to care about isInTransition at all, so this should be all that's needed:

if ( !time && utils.isBadAndroid ) {
    this.scrollerStyle[utils.style.transitionDuration] = '0.001s';
    setTimeout(function () {
        this.scrollerStyle[utils.style.transitionDuration] = '0s';
    }.bind(this), 17);
}

[sculove]

Great!. I also fix this issue like you.