Annotate ClatCoordinator with RequiresApi(T), part 2

Test: TreeHugger
Bug: 284253984
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I4994dd8d4e5e303bca6c33928d359064632b3c4d
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index fad6aaa..f10e98d 100755
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -1431,6 +1431,7 @@
         /**
          * @see ClatCoordinator
          */
+        @RequiresApi(Build.VERSION_CODES.TIRAMISU)
         public ClatCoordinator getClatCoordinator(INetd netd) {
             return new ClatCoordinator(
                 new ClatCoordinator.Dependencies() {
diff --git a/service/src/com/android/server/connectivity/Nat464Xlat.java b/service/src/com/android/server/connectivity/Nat464Xlat.java
index 2ac2ad3..90cddda 100644
--- a/service/src/com/android/server/connectivity/Nat464Xlat.java
+++ b/service/src/com/android/server/connectivity/Nat464Xlat.java
@@ -101,9 +101,9 @@
     private String mIface;
     private Inet6Address mIPv6Address;
     private State mState = State.IDLE;
-    private ClatCoordinator mClatCoordinator;
+    private final ClatCoordinator mClatCoordinator;  // non-null iff T+
 
-    private boolean mEnableClatOnCellular;
+    private final boolean mEnableClatOnCellular;
     private boolean mPrefixDiscoveryRunning;
 
     public Nat464Xlat(NetworkAgentInfo nai, INetd netd, IDnsResolver dnsResolver,
@@ -112,7 +112,11 @@
         mNetd = netd;
         mNetwork = nai;
         mEnableClatOnCellular = deps.getCellular464XlatEnabled();
-        mClatCoordinator = deps.getClatCoordinator(mNetd);
+        if (SdkLevel.isAtLeastT()) {
+            mClatCoordinator = deps.getClatCoordinator(mNetd);
+        } else {
+            mClatCoordinator = null;
+        }
     }
 
     /**