Revert of [parsing] Fix maybe-assigned for loop variables.

src/parsing/preparser.cc

Index: src/parsing/preparser.cc
diff --git a/src/parsing/preparser.cc b/src/parsing/preparser.cc
index 43877b030c764c09332f6fad89e3f1b4d806c609..0377a1b9d35e70ff9cb131ad061e01f7f257888f 100644
--- a/src/parsing/preparser.cc
+++ b/src/parsing/preparser.cc
@@ -310,14 +310,8 @@
     DCHECK(track_unresolved_variables_);
     for (auto variable : *(declaration->pattern.variables_)) {
       declaration_descriptor->scope->RemoveUnresolved(variable);
-      Variable* var = scope()->DeclareVariableName(
-          variable->raw_name(), declaration_descriptor->mode);
-      if (FLAG_preparser_scope_analysis) {
-        MarkLoopVariableAsAssigned(declaration_descriptor->scope, var);
-        // This is only necessary if there is an initializer, but we don't have
-        // that information here.  Consequently, the preparser sometimes says
-        // maybe-assigned where the parser (correctly) says never-assigned.
-      }
+      scope()->DeclareVariableName(variable->raw_name(),
+                                   declaration_descriptor->mode);
       if (names) {
         names->Add(variable->raw_name(), zone());
       }