[parser] Reverted bitfield change

Removing bitfields because they regressed code-load performance on arm.

Bug: v8:7926
Change-Id: Id7f8b26b76203c6a45ba408945abb1a2d1ad9d5b
Reviewed-on: https://chromium-review.googlesource.com/1186419Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Florian Sattler <sattlerf@google.com>
Cr-Commit-Position: refs/heads/master@{#55352}

src/parsing/parser-base.h

@@ -598,12 +598,12 @@ class ParserBase {
     typename Types::ClassPropertyList instance_fields;
     FunctionLiteralT constructor;
 
-    bool has_seen_constructor : 1;
-    bool has_name_static_property : 1;
-    bool has_static_computed_names : 1;
-    bool has_static_class_fields : 1;
-    bool has_instance_class_fields : 1;
-    bool is_anonymous : 1;
+    bool has_seen_constructor;
+    bool has_name_static_property;
+    bool has_static_computed_names;
+    bool has_static_class_fields;
+    bool has_instance_class_fields;
+    bool is_anonymous;
     DeclarationScope* static_fields_scope;
     DeclarationScope* instance_fields_scope;
     int computed_field_count;