FIX  FLEX-33166 Mobile TextInput with native StageTextInput cannot be included in scrollable forms
- fixed issue when moving from one text input to another, the sof keyboard now does not "flicker"
- to fix the above issue, has to start TI edition on mousedown instead of mouseclick (like in StyleableStageText)
- fix above (because of the change above) => TI cannot initiate a touch scroll (you have to click oustide)

Mustella tests PASS:
Mobile/components/TextInput
Mobile/components/TextArea
Mobile/Softkeyboard