Cleanup: Add more conversion helpers for usage.

Source/core/dom/Node.cpp

Index: Source/core/dom/Node.cpp
diff --git a/Source/core/dom/Node.cpp b/Source/core/dom/Node.cpp
index 6bea5c1e67110e84b44eef0523eb5b53e3fed655..fd8b48b59ebf2ac71df8c9202ceca3351fa3ff6d 100644
--- a/Source/core/dom/Node.cpp
+++ b/Source/core/dom/Node.cpp
@@ -2386,9 +2386,10 @@ void Node::defaultEventHandler(Event* event)
         if (Page* page = document().page())
             page->contextMenuController().handleContextMenuEvent(event);
     } else if (eventType == eventNames().textInputEvent) {
-        if (event->hasInterface(eventNames().interfaceForTextEvent))
+        if (event->hasInterface(eventNames().interfaceForTextEvent)) {
             if (Frame* frame = document().frame())
-                frame->eventHandler()->defaultTextInputEventHandler(static_cast<TextEvent*>(event));
+                frame->eventHandler()->defaultTextInputEventHandler(toTextEvent(event));
+        }
 #if OS(WIN)
     } else if (eventType == eventNames().mousedownEvent && event->isMouseEvent()) {
         MouseEvent* mouseEvent = toMouseEvent(event);
@@ -2407,7 +2408,7 @@ void Node::defaultEventHandler(Event* event)
         }
 #endif
     } else if ((eventType == eventNames().wheelEvent || eventType == eventNames().mousewheelEvent) && event->hasInterface(eventNames().interfaceForWheelEvent)) {
-        WheelEvent* wheelEvent = static_cast<WheelEvent*>(event);
+        WheelEvent* wheelEvent = toWheelEvent(event);
 
         // If we don't have a renderer, send the wheel event to the first node we find with a renderer.
         // This is needed for <option> and <optgroup> elements so that <select>s get a wheel scroll.