[SPARK-15122] [SQL] Fix TPC-DS 41 - Normalize predicates before pulling them out

## What changes were proposed in this pull request?
The official TPC-DS 41 query currently fails because it contains a scalar subquery with a disjunctive correlated predicate (the correlated predicates were nested in ORs). This makes the `Analyzer` pull out the entire predicate which is wrong and causes the following (correct) analysis exception: `The correlated scalar subquery can only contain equality predicates`

This PR fixes this by first simplifing (or normalizing) the correlated predicates before pulling them out of the subquery.

## How was this patch tested?
Manual testing on TPC-DS 41, and added a test to SubquerySuite.

Author: Herman van Hovell <hvanhovell@questtec.nl>

Closes #12954 from hvanhovell/SPARK-15122.

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala

@@ -26,6 +26,7 @@ import org.apache.spark.sql.catalyst.catalog.{InMemoryCatalog, SessionCatalog}
 import org.apache.spark.sql.catalyst.encoders.OuterScopes
 import org.apache.spark.sql.catalyst.expressions._
 import org.apache.spark.sql.catalyst.expressions.aggregate._
+import org.apache.spark.sql.catalyst.optimizer.BooleanSimplification
 import org.apache.spark.sql.catalyst.planning.IntegerIndex
 import org.apache.spark.sql.catalyst.plans._
 import org.apache.spark.sql.catalyst.plans.logical.{LogicalPlan, _}
@@ -958,7 +959,8 @@ class Analyzer(
         localPredicateReferences -- p.outputSet
       }
 
-      val transformed = sub transformUp {
+      // Simplify the predicates before pulling them out.
+      val transformed = BooleanSimplification(sub) transformUp {
         case f @ Filter(cond, child) =>
           // Find all predicates with an outer reference.
           val (correlated, local) = splitConjunctivePredicates(cond).partition(containsOuter)

sql/core/src/test/scala/org/apache/spark/sql/SubquerySuite.scala

@@ -281,4 +281,16 @@ class SubquerySuite extends QueryTest with SharedSQLContext {
     assert(msg1.getMessage.contains(
       "The correlated scalar subquery can only contain equality predicates"))
   }
+
+  test("disjunctive correlated scalar subquery") {
+    checkAnswer(
+      sql("""
+        |select a
+        |from   l
+        |where  (select count(*)
+        |        from   r
+        |        where (a = c and d = 2.0) or (a = c and d = 1.0)) > 0
+        """.stripMargin),
+      Row(3) :: Nil)
+  }
 }