[SPARK-19010][CORE] Include Kryo exception in case of overflow

## What changes were proposed in this pull request?

This is to workaround an implicit result of #4947 which suppressed the
original Kryo exception if the overflow happened during serialization.

## How was this patch tested?

`KryoSerializerSuite` was augmented to reflect this change.

Author: Sergei Lebedev <superbobry@gmail.com>

Closes #16416 from superbobry/patch-1.

core/src/main/scala/org/apache/spark/serializer/KryoSerializer.scala

@@ -313,7 +313,7 @@ private[spark] class KryoSerializerInstance(ks: KryoSerializer, useUnsafe: Boole
     } catch {
       case e: KryoException if e.getMessage.startsWith("Buffer overflow") =>
         throw new SparkException(s"Kryo serialization failed: ${e.getMessage}. To avoid this, " +
-          "increase spark.kryoserializer.buffer.max value.")
+          "increase spark.kryoserializer.buffer.max value.", e)
     } finally {
       releaseKryo(kryo)
     }

core/src/test/scala/org/apache/spark/serializer/KryoSerializerSuite.scala

@@ -23,7 +23,7 @@ import scala.collection.JavaConverters._
 import scala.collection.mutable
 import scala.reflect.ClassTag
 
-import com.esotericsoftware.kryo.Kryo
+import com.esotericsoftware.kryo.{Kryo, KryoException}
 import com.esotericsoftware.kryo.io.{Input => KryoInput, Output => KryoOutput}
 import org.roaringbitmap.RoaringBitmap
 
@@ -351,6 +351,7 @@ class KryoSerializerSuite extends SparkFunSuite with SharedSparkContext {
     val ser = new KryoSerializer(conf).newInstance()
     val thrown = intercept[SparkException](ser.serialize(largeObject))
     assert(thrown.getMessage.contains(kryoBufferMaxProperty))
+    assert(thrown.getCause.isInstanceOf[KryoException])
   }
 
   test("SPARK-12222: deserialize RoaringBitmap throw Buffer underflow exception") {