timob-12139: moved setText() from onTextChanged to afterTextChanged to fix the crash. fixed the "change"event.
timob-12139: add comments
timob-12139: address comments
Merge pull request #4193 from pingwang2011/timob-12139_3_1_X

Timob 12139 3 1 x: Android: Textfield change event behaves differently in 2.1.4 and 3.0.0 SDK