[regexp] allow loose matching for property names.

src/char-predicates-inl.h

Index: src/char-predicates-inl.h
diff --git a/src/char-predicates-inl.h b/src/char-predicates-inl.h
index e6cab59921c12443cbb624f58d1a605ac5625b55..ab5caa755732155d367903f1984cf168f4ab3ef3 100644
--- a/src/char-predicates-inl.h
+++ b/src/char-predicates-inl.h
@@ -43,10 +43,6 @@ inline bool IsAlphaNumeric(uc32 c) {
   return IsInRange(AsciiAlphaToLower(c), 'a', 'z') || IsDecimalDigit(c);
 }
 
-inline bool IsAlpha(uc32 c) {
-  return IsInRange(AsciiAlphaToLower(c), 'a', 'z');
-}
-
 inline bool IsDecimalDigit(uc32 c) {
   // ECMA-262, 3rd, 7.8.3 (p 16)
   return IsInRange(c, '0', '9');