Update getSignalStrengthThresholds for multilayer

Update ConnectivityService.getSignalStrengthThresholds so that
thresholds are created for multilayer requests.

Bug: 173650494
Bug: 171991028
Test: atest FrameworksNetTests
atest FrameworksNetIntegrationTests
atest CtsNetTestCasesLatestSdk

Change-Id: Ib3b9f52cf371efd1c7d9b176565c7ea8c46375f1
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index 3e66990..be44647 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -5557,13 +5557,15 @@
         mAppOpsManager.checkPackage(callerUid, callerPackageName);
     }
 
-    private ArrayList<Integer> getSignalStrengthThresholds(NetworkAgentInfo nai) {
+    private ArrayList<Integer> getSignalStrengthThresholds(@NonNull final NetworkAgentInfo nai) {
         final SortedSet<Integer> thresholds = new TreeSet<>();
         synchronized (nai) {
-            for (NetworkRequestInfo nri : mNetworkRequests.values()) {
-                if (nri.request.networkCapabilities.hasSignalStrength() &&
-                        nai.satisfiesImmutableCapabilitiesOf(nri.request)) {
-                    thresholds.add(nri.request.networkCapabilities.getSignalStrength());
+            for (final NetworkRequestInfo nri : mNetworkRequests.values()) {
+                for (final NetworkRequest req : nri.mRequests) {
+                    if (req.networkCapabilities.hasSignalStrength()
+                            && nai.satisfiesImmutableCapabilitiesOf(req)) {
+                        thresholds.add(req.networkCapabilities.getSignalStrength());
+                    }
                 }
             }
         }