[SPARK-13823][CORE][STREAMING][SQL] Always specify Charset in String <-> byte[] conversions (and remaining Coverity items)

## What changes were proposed in this pull request?

- Fixes calls to `new String(byte[])` or `String.getBytes()` that rely on platform default encoding, to use UTF-8
- Same for `InputStreamReader` and `OutputStreamWriter` constructors
- Standardizes on UTF-8 everywhere
- Standardizes specifying the encoding with `StandardCharsets.UTF-8`, not the Guava constant or "UTF-8" (which means handling `UnuspportedEncodingException`)
- (also addresses the other remaining Coverity scan issues, which are pretty trivial; these are separated into commit https://github.com/srowen/spark/commit/1deecd8d9ca986d8adb1a42d315890ce5349d29c )

## How was this patch tested?

Jenkins tests

Author: Sean Owen <sowen@cloudera.com>

Closes #11657 from srowen/SPARK-13823.

1 files changed, 2 insertions, 2 deletions

diff --git a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaUtils.scala b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaUtils.scala
index 0cb875c975..72d9053355 100644
--- a/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaUtils.scala
+++ b/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaUtils.scala
@@ -19,12 +19,12 @@ package org.apache.spark.streaming.kafka
 
 import java.io.OutputStream
 import java.lang.{Integer => JInt, Long => JLong}
+import java.nio.charset.StandardCharsets
 import java.util.{List => JList, Map => JMap, Set => JSet}
 
 import scala.collection.JavaConverters._
 import scala.reflect.ClassTag
 
-import com.google.common.base.Charsets.UTF_8
 import kafka.common.TopicAndPartition
 import kafka.message.MessageAndMetadata
 import kafka.serializer.{Decoder, DefaultDecoder, StringDecoder}
@@ -787,7 +787,7 @@ private object KafkaUtilsPythonHelper {
     def pickle(obj: Object, out: OutputStream, pickler: Pickler) {
       if (obj == this) {
         out.write(Opcodes.GLOBAL)
-        out.write(s"$module\nKafkaMessageAndMetadata\n".getBytes(UTF_8))
+        out.write(s"$module\nKafkaMessageAndMetadata\n".getBytes(StandardCharsets.UTF_8))
       } else {
         pickler.save(this)
         val msgAndMetaData = obj.asInstanceOf[PythonMessageAndMetadata]