[FLINK-3430] Remove "no POJO" warning in TypeAnalyzer

This closes apache#1655

flink-scala/src/main/scala/org/apache/flink/api/scala/codegen/TypeAnalyzer.scala

@@ -153,9 +153,6 @@ private[flink] trait TypeAnalyzer[C <: Context] { this: MacroContextHolder[C]
  val immutableFields = tpe.members filter { _.isTerm } map { _.asTerm } filter { _.isVal }
  if (immutableFields.nonEmpty) {
  // We don't support POJOs with immutable fields
- c.warning(
- c.enclosingPosition,
- s"Type $tpe is no POJO, has immutable fields: ${immutableFields.mkString(", ")}.")
  return GenericClassDescriptor(id, tpe)
  }
 
@@ -180,8 +177,6 @@ private[flink] trait TypeAnalyzer[C <: Context] { this: MacroContextHolder[C]
  }
 
  if (invalidFields.nonEmpty) {
- c.warning(c.enclosingPosition, s"Type $tpe is no POJO because it has non-public fields '" +
- s"${invalidFields.mkString(", ")}' that don't have public getters/setters.")
  return GenericClassDescriptor(id, tpe)
  }
 
@@ -194,9 +189,6 @@ private[flink] trait TypeAnalyzer[C <: Context] { this: MacroContextHolder[C]
 
  if (!hasZeroCtor) {
  // We don't support POJOs without zero-paramter ctor
- c.warning(
- c.enclosingPosition,
- s"Class $tpe is no POJO, has no zero-parameters constructor.")
  return GenericClassDescriptor(id, tpe)
  }