Enforce cross user permission to queryContentProviders api

The cl fixes the api allowing application to query providers
installed in other user without holding cross user permission if the
given process name is not null.

Bug: 237405034
Test: atest CrossUserPackageVisibilityTests
Change-Id: I79aa15de7599aadf6f4e0ce7ce7885ba7effb5cb

services/core/java/com/android/server/pm/ComputerEngine.java

@@ -5008,6 +5008,8 @@ public class ComputerEngine implements Computer {
         final int callingUid = Binder.getCallingUid();
         final int userId = processName != null ? UserHandle.getUserId(uid)
                 : UserHandle.getCallingUserId();
+        enforceCrossUserPermission(callingUid, userId, false /* requireFullPermission */,
+                false /* checkShell */, "queryContentProviders");
         if (!mUserManager.exists(userId)) return ParceledListSlice.emptyList();
         flags = updateFlagsForComponent(flags, userId);
         ArrayList<ProviderInfo> finalList = null;