Add methods to get metered override and persistence config in string

This patch adds methods to get metered override and persistence config
in human readable string in EthernetConfiguration.
This allows more informative logging.

Bug: 397536853
Test: atest ConnectivityCoverageTests
Flag: EXEMPT mainline
Change-Id: Ia5a2f4b9f624bfc1c96b197533426925dacfa554

framework-t/src/android/net/EthernetConfiguration.java

@@ -160,8 +160,36 @@ public class EthernetConfiguration implements Parcelable {
     public String toString() {
         return "IP configurations: " + mIpConfiguration
                 + "Network capabilities: " + mNetworkCapabilities
-                + ", Metered override: " + mMeteredOverride
-                + ", Is persisted: " + mPersistence;
+                + ", Metered override: " + getMeteredOverrideString()
+                + ", Is persisted: " + getPersistenceString();
+    }
+
+    /** Get metered override configuration in human readable string. */
+    private String getMeteredOverrideString() {
+        switch(mMeteredOverride) {
+            case METERED_OVERRIDE_NONE:
+                return "NONE";
+            case METERED_OVERRIDE_FORCE_METERED:
+                return "FORCE_METERED";
+            case METERED_OVERRIDE_FORCE_UNMETERED:
+                return "FORCE_UNMETERED";
+            default:
+                // We should not reach this branch.
+                return "UNKNOWN";
+        }
+    }
+
+    /** Get persistence configuration in human readable string. */
+    private String getPersistenceString() {
+        switch(mPersistence) {
+            case PERSISTENCE_IS_PERSISTED:
+                return "IS_PERSISTED";
+            case PERSISTENCE_NOT_PERSISTED:
+                return "NOT_PERSISTED";
+            default:
+                // We should not reach this branch.
+                return "UNKNOWN";
+        }
     }
 
     @Override