Revert of Simplify form validation handling

Source/core/html/HTMLFormControlElement.h

Index: Source/core/html/HTMLFormControlElement.h
diff --git a/Source/core/html/HTMLFormControlElement.h b/Source/core/html/HTMLFormControlElement.h
index eba4a9f1357a8d11d90f291abc02af68f66a6288..d068974546ca51b847689b2cbd4ab4e136573f0e 100644
--- a/Source/core/html/HTMLFormControlElement.h
+++ b/Source/core/html/HTMLFormControlElement.h
@@ -34,6 +34,7 @@
 class ValidationMessageClient;
 
 enum CheckValidityEventBehavior { CheckValidityDispatchNoEvent, CheckValidityDispatchInvalidEvent };
+enum ValidityRecalcReason { ElementAddition, ElementRemoval, ElementModification };
 
 // HTMLFormControlElement is the default implementation of FormAssociatedElement,
 // and form-associated element implementations should use HTMLFormControlElement
@@ -168,7 +169,9 @@
     ValidationMessageClient* validationMessageClient() const;
 
     // Requests validity recalc for the form owner, if one exists.
-    void formOwnerSetNeedsValidityCheck();
+    // In case of removal, isValid specifies element validity upon removal.
+    // In case of addition and modification, it specifies new validity.
+    void formOwnerSetNeedsValidityCheck(ValidityRecalcReason, bool isValid);
     // Requests validity recalc for all ancestor fieldsets, if exist.
     void fieldSetAncestorsSetNeedsValidityCheck(Node*);
 
@@ -190,8 +193,8 @@
     mutable bool m_willValidate : 1;
 
     // Cache of valid().
+    // But "candidate for constraint validation" doesn't affect m_isValid.
     bool m_isValid : 1;
-    bool m_validityIsDirty : 1;
 
     bool m_wasChangedSinceLastFormControlChangeEvent : 1;
     bool m_wasFocusedByMouse : 1;