Add toString() method for NetworkScanResult

To enhance debug-ability of NetworkScanResult, the
toString() method should return the contents of the
structure rather than a stringified reference.

Bug: 119055885
Test: NetworkScanResultTest#testParcel
Change-Id: Ib4fce53d57d1a1cd3382c65fc2c8cb1b7d6ea92d

telephony/java/com/android/internal/telephony/NetworkScanResult.java

@@ -19,6 +19,7 @@ package com.android.internal.telephony;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.telephony.CellInfo;
+
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
@@ -105,6 +106,17 @@ public final class NetworkScanResult implements Parcelable {
                 && networkInfos.equals(nsr.networkInfos));
     }
 
+    @Override
+    public String toString() {
+        return new StringBuilder()
+            .append("{")
+            .append("scanStatus=" + scanStatus)
+            .append(", scanError=" + scanError)
+            .append(", networkInfos=" + networkInfos)
+            .append("}")
+            .toString();
+    }
+
     @Override
     public int hashCode () {
         return ((scanStatus * 31)