[SPARK-13651] Generator outputs are not resolved correctly resulting in run time error

## What changes were proposed in this pull request?

```
Seq(("id1", "value1")).toDF("key", "value").registerTempTable("src")
sqlContext.sql("SELECT t1.* FROM src LATERAL VIEW explode(map('key1', 100, 'key2', 200)) t1 AS key, value")
```
Results in following logical plan

```
Project [key#2,value#3]
+- Generate explode(HiveGenericUDF#org.apache.hadoop.hive.ql.udf.generic.GenericUDFMap(key1,100,key2,200)), true, false, Some(genoutput), [key#2,value#3]
   +- SubqueryAlias src
      +- Project [_1#0 AS key#2,_2#1 AS value#3]
         +- LocalRelation [_1#0,_2#1], [[id1,value1]]
```

The above query fails with following runtime error.
```
java.lang.ClassCastException: java.lang.Integer cannot be cast to org.apache.spark.unsafe.types.UTF8String
	at org.apache.spark.sql.catalyst.expressions.BaseGenericInternalRow$class.getUTF8String(rows.scala:46)
	at org.apache.spark.sql.catalyst.expressions.GenericInternalRow.getUTF8String(rows.scala:221)
	at org.apache.spark.sql.catalyst.expressions.GeneratedClass$SpecificUnsafeProjection.apply(generated.java:42)
	at org.apache.spark.sql.execution.Generate$$anonfun$doExecute$1$$anonfun$apply$9.apply(Generate.scala:98)
	at org.apache.spark.sql.execution.Generate$$anonfun$doExecute$1$$anonfun$apply$9.apply(Generate.scala:96)
	at scala.collection.Iterator$$anon$11.next(Iterator.scala:370)
	at scala.collection.Iterator$$anon$11.next(Iterator.scala:370)
	at scala.collection.Iterator$class.foreach(Iterator.scala:742)
	at scala.collection.AbstractIterator.foreach(Iterator.scala:1194)
        <stack-trace omitted.....>
```
In this case the generated outputs are wrongly resolved from its child (LocalRelation) due to
https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L537-L548
## How was this patch tested?

(Please explain how this patch was tested. E.g. unit tests, integration tests, manual tests)

Added unit tests in hive/SQLQuerySuite and AnalysisSuite

Author: Dilip Biswal <dbiswal@us.ibm.com>

Closes #11497 from dilipbiswal/spark-13651.