title: kotlin default value in data class is aways zero
body: <p>I've a simple data class of User</p>
  
  <pre><code>data class User(@PrimaryKey(autoGenerate = true) val id: Long, val _id: String, val name: String, val about: String,
                      val phoneNumber: String, val token: String,
                      val lastLogin: String, val avatarUrl: String, @Embedded val location: Location,
                      val emailId: String, val gender: Boolean, val timestamp: Long = System.currentTimeMillis())
  </code></pre>
  
  <p>As you can see the last parameter is  <code>val timestamp: Long = System.currentTimeMillis()</code></p>
  
  <p>the response comes from network using retrofit and parsed using <code>GSON</code> </p>
  
  <p><code>timestamp</code> does not comes in a response json it's just extra field I need to do some logic. The problem is that value is always <code>0</code>. It should be the current time stamp</p>