Merge "Revert "Revert "Add testHttpEngine_EnableHttpCache""" am: 21af035644 am: 76260a9d89 am: 628ca5623e

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2463195

Change-Id: Ia864dc2ed71e32dc85dd5f3f873c6f7d8eed7ca9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>