Tell parser to skip pollsensor events by default, for the sake of J2ME

FB129304.

@ctsims I'm not certain whether the other PR, into master, is necessary or not (are we merging 2.14 back into master?) but I'm fairly certain that a PR into 2.14 *is* necessary.
*the* xforms namespace is http://www.w3.org/2002/xforms, yes?