[Effen] Port fn.dart from the legacy sky.Node backend to the RenderNode backend, which is currently…

sky/framework/components/ink_splash.dart

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 import '../animation/animated_value.dart';
 import '../animation/curves.dart';
 import '../fn.dart';
 import '../theme/view_configuration.dart' as config;
 import 'dart:async';
 import 'dart:math' as math;
-import 'dart:sky' as sky;
+import '../layout.dart';
 
 const double _kSplashConfirmedDuration = 350.0;
 const double _kSplashUnconfirmedDuration = config.kDefaultLongPressTimeout;
 const double _kSplashAbortDuration = 100.0;
 const double _kSplashInitialDelay = 0.0; // we could delay initially in case the user scrolls
 
-double _getSplashTargetSize(sky.ClientRect rect, double x, double y) {
-  return 2.0 * math.max(math.max(x - rect.left, rect.right - x),
-                        math.max(y - rect.top, rect.bottom - y));
+double _getSplashTargetSize(Rect rect, double x, double y) {
+  return 2.0 * math.max(math.max(x - rect.x, rect.x + rect.width - x),
+                        math.max(y - rect.y, rect.y + rect.height - y));
 }
 
 class SplashController {
   final int pointer;
   Stream<String> get onStyleChanged => _styleStream;
 
   final AnimatedValue _size = new AnimatedValue(0.0);
   double _offsetX;
   double _offsetY;
   double _lastSize = 0.0;
@@ skipping 18 matching lines @@
     double durationRemaining = _size.remainingTime;
     if (durationRemaining <= _kSplashAbortDuration)
       return;
     _size.animateTo(_targetSize, _kSplashAbortDuration, curve: easeOut);
   }
 
   void cancel() {
     _size.stop();
   }
 
-  SplashController(sky.ClientRect rect, double x, double y,
+  SplashController(Rect rect, double x, double y,
                    { this.pointer, Function onDone })
-      : _offsetX = x - rect.left,
-        _offsetY = y - rect.top,
+      : _offsetX = x - rect.x,
+        _offsetY = y - rect.y,
         _targetSize = _getSplashTargetSize(rect, x, y) {
 
     _styleStream = _size.onValueChanged.map((p) {
       if (p == _targetSize) {
         onDone();
       }
       double size;
       if (_growing) {
         size = p;
         _lastSize = p;
@@ skipping 59 matching lines @@
       style: _clipperStyle,
       children: [
         new Container(
           inlineStyle: _inlineStyle,
           style: _splashStyle
         )
       ]
     );
   }
 }