fix stepping over ExpressionStatementNodes

Author: timfel

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/expression/ExpressionNode.java

@@ -65,6 +65,7 @@ public static final class ExpressionStatementNode extends StatementNode {
 
         private ExpressionStatementNode(ExpressionNode node) {
             this.node = node;
+            this.assignSourceSection(node.getSourceSection());
         }
 
         @Override
@@ -89,6 +90,7 @@ public static final class ExpressionWithSideEffects extends ExpressionNode {
         private ExpressionWithSideEffects(ExpressionNode node, StatementNode sideEffect) {
             this.node = node;
             this.sideEffect = sideEffect;
+            this.assignSourceSection(node.getSourceSection());
         }
 
         @Override

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/statement/StatementNode.java

@@ -26,7 +26,6 @@
 package com.oracle.graal.python.nodes.statement;
 
 import com.oracle.graal.python.nodes.PNode;
-import com.oracle.graal.python.nodes.expression.ExpressionNode;
 import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.frame.VirtualFrame;
 import com.oracle.truffle.api.instrumentation.GenerateWrapper;
@@ -44,23 +43,6 @@ public abstract class StatementNode extends PNode {
 
     public abstract void executeVoid(VirtualFrame frame);
 
-    private static final class ExprStatementNode extends StatementNode {
-        @Child private ExpressionNode expressionNode;
-
-        private ExprStatementNode(ExpressionNode expressionNode) {
-            this.expressionNode = expressionNode;
-        }
-
-        @Override
-        public void executeVoid(VirtualFrame frame) {
-            expressionNode.execute(frame);
-        }
-    }
-
-    public StatementNode createStatementFromExpression(ExpressionNode node) {
-        return new ExprStatementNode(node);
-    }
-
     public void markAsTryBlock() {
         isTryBlock = true;
     }