Merge "Update javadoc of CarrierConfigManager" am: 540d638718 am: e994932ccc am: 874d08f1b5 am: d5cf5ae0b4

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1878021

Change-Id: I2d8e509bd172111a266edaea4865a232f8ade805