Bug 1606043 - Make TextControlState::SetValueWithoutTextEditor() notify the text control element of value changed before dispatching eEditorInput event r=smaug

I made `nsContentUtils::DispatchInputEvent()` update validity of event target
before dispatching `eEditorInput` event in bug 1584963.  However, this is not
enough because it updates validity only when the type of `<input>` element is
`mail`, but it's required for other types, for example, `<input required>`.

This patch reverts the hack added in bug 1584963, instead, makes
`TextControlState::SetValueWithoutTextEditor()` notifies `TextControlElement`
of value change before dispatching `eEditorInput` event because it may have made
damage to the performance if `nsContentUtils::DispatchInputEvent()` updated
**all** validity state of the event target.

Differential Revision: https://phabricator.services.mozilla.com/D60828

dom/html/TextControlState.cpp

@@ -3036,6 +3036,12 @@ bool TextControlState::SetValueWithoutTextEditor(
     //     event listener?
     if (aHandlingSetValue.GetSetValueFlags() & eSetValue_BySetUserInput) {
       MOZ_ASSERT(aHandlingSetValue.GetTextControlElement());
+
+      // Update validity state before dispatching "input" event for its
+      // listeners like `EditorBase::NotifyEditorObservers()`.
+      aHandlingSetValue.GetTextControlElement()->OnValueChanged(
+          true, ValueChangeKind::UserInteraction);
+
       MOZ_ASSERT(!aHandlingSetValue.GetSettingValue().IsVoid());
       DebugOnly<nsresult> rvIgnored = nsContentUtils::DispatchInputEvent(
           MOZ_KnownLive(aHandlingSetValue.GetTextControlElement()),