Add a function to process LinkProperties coming from an agent.

There are tasks that need to be performed when receiving
LinkProperties directly from a NetworkAgent (either at
registration time or in subsequent updates).

Currently, the only example of such a task is calling
ensureDirectlyConnectedRoutes. This is currently done in
handleUpdateLinkProperties, which is often unnecessary,
because that method iscalled in many other cases than when
receiving properties directly from an agent. Ensuring directly
connected routes only needs to be done when receiving
LinkProperties from the agent, because ConnectivityService does
not directly manipulate routes.

This CL does not do much except remove these superfluous calls
and add the method. A future CL will add more code to the method.

Bug: 150648313
Test: atest ConnectivityServiceTest
Change-Id: Ibeeb5f79e8afd3350c935934713d7882f2e0281f
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index ea91395..651fa41 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -2712,7 +2712,9 @@
                     break;
                 }
                 case NetworkAgent.EVENT_NETWORK_PROPERTIES_CHANGED: {
-                    handleUpdateLinkProperties(nai, (LinkProperties) msg.obj);
+                    LinkProperties newLp = (LinkProperties) msg.obj;
+                    processLinkPropertiesFromAgent(nai, newLp);
+                    handleUpdateLinkProperties(nai, newLp);
                     break;
                 }
                 case NetworkAgent.EVENT_NETWORK_INFO_CHANGED: {
@@ -5805,7 +5807,7 @@
         }
 
         LinkProperties lp = new LinkProperties(linkProperties);
-        lp.ensureDirectlyConnectedRoutes();
+
         // TODO: Instead of passing mDefaultRequest, provide an API to determine whether a Network
         // satisfies mDefaultRequest.
         final NetworkCapabilities nc = new NetworkCapabilities(networkCapabilities);
@@ -5813,8 +5815,11 @@
                 new Network(mNetIdManager.reserveNetId()), new NetworkInfo(networkInfo), lp, nc,
                 currentScore, mContext, mTrackerHandler, new NetworkAgentConfig(networkAgentConfig),
                 this, mNetd, mDnsResolver, mNMS, providerId);
-        // Make sure the network capabilities reflect what the agent info says.
+
+        // Make sure the LinkProperties and NetworkCapabilities reflect what the agent info says.
         nai.getAndSetNetworkCapabilities(mixInCapabilities(nai, nc));
+        processLinkPropertiesFromAgent(nai, nai.linkProperties);
+
         final String extraInfo = networkInfo.getExtraInfo();
         final String name = TextUtils.isEmpty(extraInfo)
                 ? nai.networkCapabilities.getSsid() : extraInfo;
@@ -5852,6 +5857,10 @@
         updateUids(nai, null, nai.networkCapabilities);
     }
 
+    private void processLinkPropertiesFromAgent(NetworkAgentInfo nai, LinkProperties lp) {
+        lp.ensureDirectlyConnectedRoutes();
+    }
+
     private void updateLinkProperties(NetworkAgentInfo networkAgent, LinkProperties newLp,
             @NonNull LinkProperties oldLp) {
         int netId = networkAgent.network.netId;
@@ -6369,13 +6378,13 @@
             // Ignore updates for disconnected networks
             return;
         }
-        // newLp is already a defensive copy.
-        newLp.ensureDirectlyConnectedRoutes();
         if (VDBG || DDBG) {
             log("Update of LinkProperties for " + nai.toShortString()
                     + "; created=" + nai.created
                     + "; everConnected=" + nai.everConnected);
         }
+        // TODO: eliminate this defensive copy after confirming that updateLinkProperties does not
+        // modify its oldLp parameter.
         updateLinkProperties(nai, newLp, new LinkProperties(nai.linkProperties));
     }