refine class naming

Runtime/cupertino/dialog.cs

     }
 
     class _CupertinoDialogRenderElement : RenderObjectElement {
-        public _CupertinoDialogRenderElement(_CupertinoDialogRenderWidget widget) : base(widget) { }
+        public _CupertinoDialogRenderElement(_CupertinoDialogRenderWidget widget) : base(widget) {
+        }
 
         Element _contentElement;
         Element _actionsElement;
             List<Widget> interactiveButtons = new List<Widget>();
             for (int i = 0; i < this.widget.children.Count; i += 1) {
                 interactiveButtons.Add(
-                    new _PressableActionButton(
+                    new _PressableDialogActionButton(
                         child: this.widget.children[i]
                     )
                 );
         }
     }
 
-    class _PressableActionButton : StatefulWidget {
-        public _PressableActionButton(
+    class _PressableDialogActionButton : StatefulWidget {
+        public _PressableDialogActionButton(
             Widget child
         ) {
             this.child = child;
 
         public override State createState() {
-            return new _PressableActionButtonState();
+            return new _PressableDialogActionButtonState();
-    class _PressableActionButtonState : State<_PressableActionButton> {
+    class _PressableDialogActionButtonState : State<_PressableDialogActionButton> {
-            return new _ActionButtonParentDataWidget(
+            return new _DialogActionButtonParentDataWidget(
                 isPressed: this._isPressed,
                 child: new GestureDetector(
                     behavior: HitTestBehavior.opaque,
         }
     }
 
-    class _ActionButtonParentDataWidget : ParentDataWidget<_CupertinoDialogActionsRenderWidget> {
-        public _ActionButtonParentDataWidget(
+    class _DialogActionButtonParentDataWidget : ParentDataWidget<_CupertinoDialogActionsRenderWidget> {
+        public _DialogActionButtonParentDataWidget(
             Widget child,
             bool isPressed = false,
             Key key = null
         public readonly bool isPressed;
 
         public override void applyParentData(RenderObject renderObject) {
-            D.assert(renderObject.parentData is _ActionButtonParentData);
-            _ActionButtonParentData parentData = renderObject.parentData as _ActionButtonParentData;
+            D.assert(renderObject.parentData is _DialogActionButtonParentData);
+            _DialogActionButtonParentData parentData = renderObject.parentData as _DialogActionButtonParentData;
             if (parentData.isPressed != this.isPressed) {
                 parentData.isPressed = this.isPressed;
                 AbstractNodeMixinDiagnosticableTree targetParent = renderObject.parent;
         }
     }
 
-    class _ActionButtonParentData : MultiChildLayoutParentData {
-        public _ActionButtonParentData(
+    class _DialogActionButtonParentData : MultiChildLayoutParentData {
+        public _DialogActionButtonParentData(
             bool isPressed = false
         ) {
             this.isPressed = isPressed;
 
                 RenderBox currentChild = this.firstChild;
                 while (currentChild != null) {
-                    D.assert(currentChild.parentData is _ActionButtonParentData);
-                    _ActionButtonParentData parentData = currentChild.parentData as _ActionButtonParentData;
+                    D.assert(currentChild.parentData is _DialogActionButtonParentData);
+                    _DialogActionButtonParentData parentData = currentChild.parentData as _DialogActionButtonParentData;
                     if (parentData.isPressed) {
                         childList.Add(currentChild);
                     }
             get {
                 RenderBox currentChild = this.firstChild;
                 while (currentChild != null) {
-                    D.assert(currentChild.parentData is _ActionButtonParentData);
-                    _ActionButtonParentData parentData = currentChild.parentData as _ActionButtonParentData;
+                    D.assert(currentChild.parentData is _DialogActionButtonParentData);
+                    _DialogActionButtonParentData parentData = currentChild.parentData as _DialogActionButtonParentData;
                     if (parentData.isPressed) {
                         return true;
                     }
         }
 
         public override void setupParentData(RenderObject child) {
-            if (!(child.parentData is _ActionButtonParentData)) {
-                child.parentData = new _ActionButtonParentData();
+            if (!(child.parentData is _DialogActionButtonParentData)) {
+                child.parentData = new _DialogActionButtonParentData();
             }
         }
 
             RenderBox prevChild = null;
 
             while (child != null) {
-                D.assert(child.parentData is _ActionButtonParentData);
-                _ActionButtonParentData currentButtonParentData = child.parentData as _ActionButtonParentData;
+                D.assert(child.parentData is _DialogActionButtonParentData);
+                _DialogActionButtonParentData currentButtonParentData =
+                    child.parentData as _DialogActionButtonParentData;
-                    D.assert(prevChild.parentData is _ActionButtonParentData);
-                    _ActionButtonParentData previousButtonParentData = prevChild.parentData as _ActionButtonParentData;
+                    D.assert(prevChild.parentData is _DialogActionButtonParentData);
+                    _DialogActionButtonParentData previousButtonParentData =
+                        prevChild.parentData as _DialogActionButtonParentData;
                     isPrevButtonPressed = previousButtonParentData.isPressed;
                 }