Merge "Fix NPE when removing policies." into udc-dev am: f76eaf9aa3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22616876

Change-Id: I9134dc7d5362715af78c5de518f74bf4729f331c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyEngine.java

@@ -1066,6 +1066,11 @@ final class DevicePolicyEngine {
      * Removes all local policies for the provided {@code userId}.
      */
     private void removeLocalPoliciesForUser(int userId) {
+        if (!mLocalPolicies.contains(userId)) {
+            // No policies on user
+            return;
+        }
+
         Set<PolicyKey> localPolicies = new HashSet<>(mLocalPolicies.get(userId).keySet());
         for (PolicyKey policy : localPolicies) {
             PolicyState<?> policyState = mLocalPolicies.get(userId).get(policy);