[wasm] Generate source position information

src/compiler/source-position.h

Index: src/compiler/source-position.h
diff --git a/src/compiler/source-position.h b/src/compiler/source-position.h
index 1f5196d1932f194e570897e89d146bd373a994a2..912f18829f4fe7688ac52f4bba9366e3cfcb85eb 100644
--- a/src/compiler/source-position.h
+++ b/src/compiler/source-position.h
@@ -38,8 +38,7 @@ inline bool operator!=(const SourcePosition& lhs, const SourcePosition& rhs) {
   return !(lhs == rhs);
 }
 
-
-class SourcePositionTable final {
+class SourcePositionTable final : public ZoneObject {
  public:
   class Scope final {
    public:
@@ -71,6 +70,7 @@ class SourcePositionTable final {
   void RemoveDecorator();
 
   SourcePosition GetSourcePosition(Node* node) const;
+  void SetSourcePosition(Node* node, SourcePosition position);
 
   void Print(std::ostream& os) const;