[SPARK-11752] [SQL] fix timezone problem for DateTimeUtils.getSeconds

code snippet to reproduce it:
```
TimeZone.setDefault(TimeZone.getTimeZone("Asia/Shanghai"))
val t = Timestamp.valueOf("1900-06-11 12:14:50.789")
val us = fromJavaTimestamp(t)
assert(getSeconds(us) === t.getSeconds)
```

it will be good to add a regression test for it, but the reproducing code need to change the default timezone, and even we change it back, the `lazy val defaultTimeZone` in `DataTimeUtils` is fixed.

Author: Wenchen Fan <wenchen@databricks.com>

Closes #9728 from cloud-fan/seconds.

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/DateTimeUtils.scala

@@ -395,16 +395,19 @@ object DateTimeUtils {
   /**
    * Returns the microseconds since year zero (-17999) from microseconds since epoch.
    */
-  def absoluteMicroSecond(microsec: SQLTimestamp): SQLTimestamp = {
+  private def absoluteMicroSecond(microsec: SQLTimestamp): SQLTimestamp = {
     microsec + toYearZero * MICROS_PER_DAY
   }
 
+  private def localTimestamp(microsec: SQLTimestamp): SQLTimestamp = {
+    absoluteMicroSecond(microsec) + defaultTimeZone.getOffset(microsec / 1000) * 1000L
+  }
+
   /**
    * Returns the hour value of a given timestamp value. The timestamp is expressed in microseconds.
    */
   def getHours(microsec: SQLTimestamp): Int = {
-    val localTs = absoluteMicroSecond(microsec) + defaultTimeZone.getOffset(microsec / 1000) * 1000L
-    ((localTs / MICROS_PER_SECOND / 3600) % 24).toInt
+    ((localTimestamp(microsec) / MICROS_PER_SECOND / 3600) % 24).toInt
   }
 
   /**
@@ -412,8 +415,7 @@ object DateTimeUtils {
    * microseconds.
    */
   def getMinutes(microsec: SQLTimestamp): Int = {
-    val localTs = absoluteMicroSecond(microsec) + defaultTimeZone.getOffset(microsec / 1000) * 1000L
-    ((localTs / MICROS_PER_SECOND / 60) % 60).toInt
+    ((localTimestamp(microsec) / MICROS_PER_SECOND / 60) % 60).toInt
   }
 
   /**
@@ -421,7 +423,7 @@ object DateTimeUtils {
    * microseconds.
    */
   def getSeconds(microsec: SQLTimestamp): Int = {
-    ((absoluteMicroSecond(microsec) / MICROS_PER_SECOND) % 60).toInt
+    ((localTimestamp(microsec) / MICROS_PER_SECOND) % 60).toInt
   }
 
   private[this] def isLeapYear(year: Int): Boolean = {

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/util/DateTimeUtilsSuite.scala

@@ -358,7 +358,7 @@ class DateTimeUtilsSuite extends SparkFunSuite {
     assert(getSeconds(c.getTimeInMillis * 1000) === 9)
   }
 
-  test("hours / miniute / seconds") {
+  test("hours / minutes / seconds") {
     Seq(Timestamp.valueOf("2015-06-11 10:12:35.789"),
       Timestamp.valueOf("2015-06-11 20:13:40.789"),
       Timestamp.valueOf("1900-06-11 12:14:50.789"),