Move trimV4AddrZeros to libs/net

The utility is @UnsupportedAppUsage, and also used by internal classes
like WifiTrackerLib or Mms, so it needs to be in a shared location.

Bug: 182859030
Test: m
Change-Id: I25cb374f4743a5869e9da5b01d3a543a9a165c0e

framework/src/android/net/NetworkUtils.java

@@ -323,22 +323,7 @@ public class NetworkUtils {
      */
     @UnsupportedAppUsage
     public static String trimV4AddrZeros(String addr) {
-        if (addr == null) return null;
-        String[] octets = addr.split("\\.");
-        if (octets.length != 4) return addr;
-        StringBuilder builder = new StringBuilder(16);
-        String result = null;
-        for (int i = 0; i < 4; i++) {
-            try {
-                if (octets[i].length() > 3) return addr;
-                builder.append(Integer.parseInt(octets[i]));
-            } catch (NumberFormatException e) {
-                return addr;
-            }
-            if (i < 3) builder.append('.');
-        }
-        result = builder.toString();
-        return result;
+        return Inet4AddressUtils.trimAddressZeros(addr);
     }
 
     /**