Merge "Add KEY_CARRIER_USSD_METHOD_INT to specify methods for USSD requests" am: 3acec4d14f am: ac3167e3dd am: 08ab8031da

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1372476

Change-Id: I3b32442c56a5dfb79d78b2113a2a872cfeb0c72e