IMS-VT: Use original dialed string instead of normalized dial string

- The smart dial search normalizes the dial string, and removes
  anything other than digits.

- Original dial string contains the number which is actully entered
  by user. Pass this number as it is as dialed number validation is
  already taken care by APIs defined in PhoneNumberUtils.

Bug=27074055
Change-Id: Ib85750abef765ace127ebde3a13397b4dfad48fa