[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/mllib/src/test/java/org/apache/spark/ml/source/libsvm/JavaLibSVMRelationSuite.java b/mllib/src/test/java/org/apache/spark/ml/source/libsvm/JavaLibSVMRelationSuite.java
index b8ddf907d0..1c18b2b266 100644
--- a/mllib/src/test/java/org/apache/spark/ml/source/libsvm/JavaLibSVMRelationSuite.java
+++ b/mllib/src/test/java/org/apache/spark/ml/source/libsvm/JavaLibSVMRelationSuite.java
@@ -19,8 +19,8 @@ package org.apache.spark.ml.source.libsvm;
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 
-import com.google.common.base.Charsets;
 import com.google.common.io.Files;
 
 import org.junit.After;
@@ -55,7 +55,7 @@ public class JavaLibSVMRelationSuite {
     tempDir = Utils.createTempDir(System.getProperty("java.io.tmpdir"), "datasource");
     File file = new File(tempDir, "part-00000");
     String s = "1 1:1.0 3:2.0 5:3.0\n0\n0 2:4.0 4:5.0 6:6.0";
-    Files.write(s, file, Charsets.US_ASCII);
+    Files.write(s, file, StandardCharsets.UTF_8);
     path = tempDir.toURI().toString();
   }