[SPARK-13384][SQL] Keep attribute qualifiers after dedup in Analyzer

JIRA: https://issues.apache.org/jira/browse/SPARK-13384

## What changes were proposed in this pull request?

When we de-duplicate attributes in Analyzer, we create new attributes. However, we don't keep original qualifiers. Some plans will be failed to analysed. We should keep original qualifiers in new attributes.

## How was the this patch tested?

Unit test is added.

Author: Liang-Chi Hsieh <viirya@gmail.com>

Closes #11261 from viirya/keep-attr-qualifiers.

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

@@ -432,7 +432,8 @@ class Analyzer(
             case r if r == oldRelation => newRelation
           } transformUp {
             case other => other transformExpressions {
-              case a: Attribute => attributeRewrites.get(a).getOrElse(a)
+              case a: Attribute =>
+                attributeRewrites.get(a).getOrElse(a).withQualifiers(a.qualifiers)
             }
           }
           newRight

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala

@@ -21,6 +21,7 @@ import org.apache.spark.sql.catalyst.TableIdentifier
 import org.apache.spark.sql.catalyst.dsl.expressions._
 import org.apache.spark.sql.catalyst.dsl.plans._
 import org.apache.spark.sql.catalyst.expressions._
+import org.apache.spark.sql.catalyst.plans.Inner
 import org.apache.spark.sql.catalyst.plans.logical._
 import org.apache.spark.sql.types._
 
@@ -336,4 +337,17 @@ class AnalysisSuite extends AnalysisTest {
     val plan = relation.select(CaseWhen(Seq((Literal(true), 'a.attr)), 'b).as("val"))
     assertAnalysisSuccess(plan)
   }
+
+  test("Keep attribute qualifiers after dedup") {
+    val input = LocalRelation('key.int, 'value.string)
+
+    val query =
+      Project(Seq($"x.key", $"y.key"),
+        Join(
+          Project(Seq($"x.key"), Subquery("x", input)),
+          Project(Seq($"y.key"), Subquery("y", input)),
+          Inner, None))
+
+    assertAnalysisSuccess(query)
+  }
 }