Fix inconsistencies wrt whitespaces.

test/cctest/test-regexp.cc

Index: test/cctest/test-regexp.cc
diff --git a/test/cctest/test-regexp.cc b/test/cctest/test-regexp.cc
index d0193520fae9a5e225ff7d1379b4fcf61653df08..d6a11b1f044ee728e59f896906eb4f46f17cba0f 100644
--- a/test/cctest/test-regexp.cc
+++ b/test/cctest/test-regexp.cc
@@ -445,21 +445,7 @@ static bool NotDigit(uc16 c) {
 
 
 static bool IsWhiteSpace(uc16 c) {
-  switch (c) {
-    case 0x09:
-    case 0x0A:
-    case 0x0B:
-    case 0x0C:
-    case 0x0d:
-    case 0x20:
-    case 0xA0:
-    case 0x2028:
-    case 0x2029:
-    case 0xFEFF:
-      return true;
-    default:
-      return unibrow::Space::Is(c);
-  }
+  return CcTest::i_isolate()->unicode_cache()->IsWhiteSpace(c);
 }