Merge "Guard the usage of PacProxyManager when it is not supported by the device." am: 76f61bb2e8 am: 89c7b7db4e am: b92e07b760 am: 65e78050c6

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2623371

Change-Id: I8897b9ff7c9fe696c5d1cb00be7c620d5b107ed4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>