Introduce the config to disable LAUNCH_BROWSER

LAUNCH BROWSER STK command may need to be disabled
if carrier would not want the default behavior.
So introduce a carrierconfig key for the same

Test: Swapped the sprint sim cards and verified
that browser launch do not happen.

Merged-in: Iaff062547f5286b2c0b2c2c4c6182a287f07284b
BUG=31257758
Change-Id: Iaff062547f5286b2c0b2c2c4c6182a287f07284b