Implement setValue method for AbstractTextField element class (#13365)

Implement setValue method for TextFieldElement, TextAreaElement,
PasswordFieldElement, DateFieldElement. Method do the following:
1. clear any old content without triggering a value change
2. type the specified text string into the element, which trigger
   a value change event

Change-Id: I0373feeca2539aeae375e6a3dc0f16c7d8db6970