Revert "Switch RegularExpression from YARR to V8"

Source/core/html/BaseTextInputType.cpp

Index: Source/core/html/BaseTextInputType.cpp
diff --git a/Source/core/html/BaseTextInputType.cpp b/Source/core/html/BaseTextInputType.cpp
index fd9c9e5b748ad7c458ac641039637b4bacb9c57b..9a9540f70035465b5eab3d57c83b1dd8526df30b 100644
--- a/Source/core/html/BaseTextInputType.cpp
+++ b/Source/core/html/BaseTextInputType.cpp
@@ -44,12 +44,9 @@ bool BaseTextInputType::patternMismatch(const String& value) const
     if (rawPattern.isNull() || value.isEmpty())
         return false;
     String pattern = "^(" + rawPattern + ")$";
-    RegularExpression regex(pattern, TextCaseSensitive);
-    if (!regex.isValid())
-        return false;
     int matchLength = 0;
     int valueLength = value.length();
-    int matchOffset = regex.match(value, 0, &matchLength);
+    int matchOffset = RegularExpression(pattern, TextCaseSensitive).match(value, 0, &matchLength);
     return matchOffset || matchLength != valueLength;
 }