Replace NetworkPolicyManagerInternal#isUidRestrictedOnMeteredNetworks()

Connectivity service is going to become a mainline module which
will not able to access hidden APIs. NetworkPolicyManagerInternal
is a internal serivce that CS can't be access after be a mainline
module. Thus, create NPMS#isUidRestrictedOnMeteredNetworks() and
NPM#isUidRestrictedOnMeteredNetworks() to replace
NPMI#isUidRestrictedOnMeteredNetworks().

Also correct the permission check in isUidNetworkingBlocked()
that needs to check OBSERVE_NETWORK_POLICY only.

Bug: 170598012
Test: atest FrameworksNetTests
Test: atest FrameworksCoreTests:NetworkPolicyManagerTest
Test: atest FrameworksServicesTests:NetworkPolicyManagerServiceTest
Test: atest CtsNetTestCases
Test: atest CtsHostsideNetworkTests
Change-Id: I5801a3a2076f3eb199a0226c38c85014b26c64e7
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index 7541833..ba99821 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -5777,9 +5777,14 @@
             // Policy already enforced.
             return;
         }
-        if (mPolicyManagerInternal.isUidRestrictedOnMeteredNetworks(uid)) {
-            // If UID is restricted, don't allow them to bring up metered APNs.
-            networkCapabilities.addCapability(NET_CAPABILITY_NOT_METERED);
+        final long ident = Binder.clearCallingIdentity();
+        try {
+            if (mPolicyManager.isUidRestrictedOnMeteredNetworks(uid)) {
+                // If UID is restricted, don't allow them to bring up metered APNs.
+                networkCapabilities.addCapability(NET_CAPABILITY_NOT_METERED);
+            }
+        } finally {
+            Binder.restoreCallingIdentity(ident);
         }
     }