Revert of [parser] Fix scopes in rewriting of for-of and destructuring assignments.

src/parsing/parser.cc

Index: src/parsing/parser.cc
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index e6c1c79a4159f9fa065912662d1822350f6fe221..79d06da50750fca179203bb8abd768b07043d76d 100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -4309,11 +4309,8 @@
         pair.assignment->AsRewritableExpression();
     DCHECK_NOT_NULL(to_rewrite);
     if (!to_rewrite->is_rewritten()) {
-      // Since this function is called at the end of parsing the program,
-      // pair.scope may already have been removed by FinalizeBlockScope in the
-      // meantime.
-      Scope* scope = pair.scope->GetUnremovedScope();
-      PatternRewriter::RewriteDestructuringAssignment(this, to_rewrite, scope);
+      PatternRewriter::RewriteDestructuringAssignment(this, to_rewrite,
+                                                      pair.scope);
     }
   }
 }
@@ -4748,7 +4745,7 @@
 
     Block* then = factory()->NewBlock(nullptr, 4 + 1, false, nopos);
     BuildIteratorCloseForCompletion(
-        scope(), then->statements(), var_iterator,
+        then->statements(), var_iterator,
         factory()->NewSmiLiteral(Parser::kNormalCompletion, nopos));
     then->statements()->Add(throw_call, zone());
     check_throw = factory()->NewIfStatement(
@@ -5116,9 +5113,9 @@
   statements->Add(validate_output, zone());
 }
 
-void Parser::FinalizeIteratorUse(Scope* use_scope, Variable* completion,
-                                 Expression* condition, Variable* iter,
-                                 Block* iterator_use, Block* target) {
+void Parser::FinalizeIteratorUse(Variable* completion, Expression* condition,
+                                 Variable* iter, Block* iterator_use,
+                                 Block* target) {
   //
   // This function adds two statements to [target], corresponding to the
   // following code:
@@ -5174,8 +5171,7 @@
   {
     Block* block = factory()->NewBlock(nullptr, 2, true, nopos);
     Expression* proxy = factory()->NewVariableProxy(completion);
-    BuildIteratorCloseForCompletion(use_scope, block->statements(), iter,
-                                    proxy);
+    BuildIteratorCloseForCompletion(block->statements(), iter, proxy);
     DCHECK(block->statements()->length() == 2);
 
     maybe_close = factory()->NewBlock(nullptr, 1, true, nopos);
@@ -5192,7 +5188,7 @@
   // }
   Statement* try_catch;
   {
-    Scope* catch_scope = NewScopeWithParent(use_scope, CATCH_SCOPE);
+    Scope* catch_scope = NewScopeWithParent(scope(), CATCH_SCOPE);
     Variable* catch_variable =
         catch_scope->DeclareLocal(ast_value_factory()->dot_catch_string(), VAR,
                                   kCreatedInitialized, NORMAL_VARIABLE);
@@ -5232,8 +5228,7 @@
   target->statements()->Add(try_finally, zone());
 }
 
-void Parser::BuildIteratorCloseForCompletion(Scope* scope,
-                                             ZoneList<Statement*>* statements,
+void Parser::BuildIteratorCloseForCompletion(ZoneList<Statement*>* statements,
                                              Variable* iterator,
                                              Expression* completion) {
   //
@@ -5299,7 +5294,7 @@
 
     Block* catch_block = factory()->NewBlock(nullptr, 0, false, nopos);
 
-    Scope* catch_scope = NewScopeWithParent(scope, CATCH_SCOPE);
+    Scope* catch_scope = NewScope(CATCH_SCOPE);
     Variable* catch_variable =
         catch_scope->DeclareLocal(ast_value_factory()->dot_catch_string(), VAR,
                                   kCreatedInitialized, NORMAL_VARIABLE);
@@ -5436,13 +5431,8 @@
     Block* try_block = factory()->NewBlock(nullptr, 1, false, nopos);
     try_block->statements()->Add(loop, zone());
 
-    // The scope in which the parser creates this loop.
-    Scope* loop_scope = scope()->outer_scope();
-    DCHECK_EQ(loop_scope->scope_type(), BLOCK_SCOPE);
-    DCHECK_EQ(scope()->scope_type(), BLOCK_SCOPE);
-
-    FinalizeIteratorUse(loop_scope, var_completion, closing_condition,
-                        loop->iterator(), try_block, final_loop);
+    FinalizeIteratorUse(var_completion, closing_condition, loop->iterator(),
+                        try_block, final_loop);
   }
 
   return final_loop;