Use TYPE_HANDWRITING in the example docs for View#onResolvePointerIcon

The PointerIcon style TYPE_HANDWRITING is more likely to be used
for styluses, so use that in the example of how to resolve the
pointer icon for a stylus.

Bug: 245989146
Change-Id: Ib49ad5f75c7d97b55e9ecbfdc6f9fef6c831e17e
Test: NONE
Flag: NONE docs only