[JSC] Optimize layout of RegExp to reduce padding
https://bugs.webkit.org/show_bug.cgi?id=187438

Reviewed by Mark Lam.

Reduce the size of RegExp from 168 to 144.

* runtime/RegExp.cpp:
(JSC::RegExp::RegExp):
* runtime/RegExp.h:
* runtime/RegExpKey.h:
* yarr/YarrErrorCode.h:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@233621 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/JavaScriptCore/runtime/RegExpKey.h b/Source/JavaScriptCore/runtime/RegExpKey.h
index 79b652f..d01e40a 100644
--- a/Source/JavaScriptCore/runtime/RegExpKey.h
+++ b/Source/JavaScriptCore/runtime/RegExpKey.h
@@ -32,7 +32,7 @@
 
 namespace JSC {
 
-enum RegExpFlags {
+enum RegExpFlags : int8_t {
     NoFlags = 0,
     FlagGlobal = 1,
     FlagIgnoreCase = 2,