Rename watchPerformance to watch

Now that we don't have the old animation system, we can use the shorter name
again. Also, move state initialization code into initState().

R=ianh@google.com

Review URL: https://codereview.chromium.org/1231103005 .

sdk/example/stocks/lib/stock_home.dart

@@ -286,7 +286,7 @@ class StockHome extends AnimatedComponent {
         ..position = new AnimatedType<Point>(const Point(0.0, 45.0), end: Point.origin);
       var performance = _snackbarTransform.createPerformance(
           [_snackbarTransform.position], duration: _kSnackbarSlideDuration);
-      watchPerformance(performance);
+      watch(performance);
       performance.play();
     });
   }

sdk/lib/widgets/animated_component.dart

@@ -13,7 +13,7 @@ abstract class AnimatedComponent extends StatefulComponent {
 
   final List<AnimationPerformance> _watchedPerformances = new List<AnimationPerformance>();
 
-  void watchPerformance(AnimationPerformance performance) {
+  void watch(AnimationPerformance performance) {
     assert(!_watchedPerformances.contains(performance));
     _watchedPerformances.add(performance);
     if (mounted)

sdk/lib/widgets/animated_container.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 'package:vector_math/vector_math.dart';
-
-import 'package:sky/animation/animation_performance.dart';
-import 'package:sky/animation/curves.dart';
-import 'package:sky/base/lerp.dart';
-import 'package:sky/painting/box_painter.dart';
-import 'package:sky/theme/shadows.dart';
-import 'package:sky/widgets/basic.dart';
-
-// This class builds a Builder object from a collection of optionally-
-// animated properties. Use syncFields to update the Builder's properties,
-// which will optionally animate them using an AnimationPerformance.
-class AnimationBuilder {
-  AnimatedType<double> opacity;
-  AnimatedType<Point> position;
-  AnimatedType<double> shadow;
-  AnimatedColor backgroundColor;
-
-  // These don't animate, but are used to build the AnimationBuilder anyway.
-  double borderRadius;
-  Shape shape;
-
-  Map<AnimatedVariable, AnimationPerformance> _variableToPerformance =
-      new Map<AnimatedVariable, AnimationPerformance>();
-
-  AnimationBuilder();
-
-  AnimationPerformance createPerformance(List<AnimatedType> variables,
-                                         {Duration duration}) {
-    AnimationPerformance performance = new AnimationPerformance()
-      ..duration = duration
-      ..variable = new AnimatedList(variables);
-    for (AnimatedVariable variable in variables)
-      _variableToPerformance[variable] = performance;
-    return performance;
-  }
-
-  Widget build(Widget child) {
-    Widget current = child;
-    if (shadow != null || backgroundColor != null ||
-        borderRadius != null || shape != null) {
-      current = new DecoratedBox(
-        decoration: new BoxDecoration(
-          borderRadius: borderRadius,
-          shape: shape,
-          boxShadow: shadow != null ? _computeShadow(shadow.value) : null,
-          backgroundColor: backgroundColor != null ? backgroundColor.value : null),
-        child: current);
-    }
-
-    if (position != null) {
-      Matrix4 transform = new Matrix4.identity();
-      transform.translate(position.value.x, position.value.y);
-      current = new Transform(transform: transform, child: current);
-    }
-
-    if (opacity != null) {
-      current = new Opacity(opacity: opacity.value, child: current);
-    }
-
-    return current;
-  }
-
-  void syncFields(AnimationBuilder source) {
-    _syncField(position, source.position);
-    _syncField(shadow, source.shadow);
-    _syncField(backgroundColor, source.backgroundColor);
-
-    borderRadius = source.borderRadius;
-    shape = source.shape;
-  }
-
-  void _syncField(AnimatedType variable, AnimatedType sourceVariable) {
-    if (variable == null)
-      return;  // TODO(mpcomplete): Should we handle transition from null?
-
-    AnimationPerformance performance = _variableToPerformance[variable];
-    if (performance == null) {
-      // If there's no performance, no need to animate.
-      if (sourceVariable != null)
-        variable.value = sourceVariable.value;
-      return;
-    }
-
-    if (variable.value != sourceVariable.value) {
-      variable
-        ..begin = variable.value
-        ..end = sourceVariable.value;
-      performance
-        ..progress = 0.0
-        ..play();
-    }
-  }
-}
-
-class AnimatedColor extends AnimatedType<Color> {
-  AnimatedColor(Color begin, {Color end, Curve curve: linear})
-      : super(begin, end: end, curve: curve);
-
-  void setFraction(double t) {
-    value = lerpColor(begin, end, t);
-  }
-}
-
-List<BoxShadow> _computeShadow(double level) {
-  if (level < 1.0)  // shadows[1] is the first shadow
-    return null;
-
-  int level1 = level.floor();
-  int level2 = level.ceil();
-  double t = level - level1.toDouble();
-
-  List<BoxShadow> shadow = new List<BoxShadow>();
-  for (int i = 0; i < shadows[level1].length; ++i)
-    shadow.add(lerpBoxShadow(shadows[level1][i], shadows[level2][i], t));
-  return shadow;
-}

sdk/lib/widgets/dismissable.dart

@@ -45,7 +45,7 @@ class Dismissable extends AnimatedComponent {
         [_transform.position, _transform.opacity],
         duration: new Duration(milliseconds: _kCardDismissFadeoutMS));
     _performance.addListener(_handleAnimationProgressChanged);
-    watchPerformance(_performance);
+    watch(_performance);
   }
 
   void syncFields(Dismissable source) {

sdk/lib/widgets/drawer.dart

@@ -105,14 +105,16 @@ class Drawer extends AnimatedComponent {
     this.controller,
     this.children,
     this.level: 0
-  }) : super(key: key) {
-    watchPerformance(controller.performance);
-  }
+  }) : super(key: key);
 
   List<Widget> children;
   int level;
   DrawerController controller;
 
+  void initState() {
+    watch(controller.performance);
+  }
+
   void syncFields(Drawer source) {
     children = source.children;
     level = source.level;

sdk/lib/widgets/material.dart

@@ -47,11 +47,11 @@ class Material extends AnimatedComponent {
       ..backgroundColor = _getBackgroundColor(type, color)
       ..borderRadius = edges[type]
       ..shape = type == MaterialType.circle ? Shape.circle : Shape.rectangle;
-    watchPerformance(_builder.createPerformance(
+    watch(_builder.createPerformance(
         [_builder.shadow],
         duration: _kAnimateShadowDuration
     ));
-    watchPerformance(_builder.createPerformance(
+    watch(_builder.createPerformance(
         [_builder.backgroundColor],
         duration: _kAnimateColorDuration
     ));

sdk/lib/widgets/popup_menu.dart

@@ -91,18 +91,20 @@ class PopupMenuController {
 class PopupMenu extends AnimatedComponent {
 
   PopupMenu({ String key, this.controller, this.items, this.level })
-      : super(key: key) {
+      : super(key: key);
+
+  PopupMenuController controller;
+  List<PopupMenuItem> items;
+  int level;
+
+  void initState() {
     _painter = new BoxPainter(new BoxDecoration(
       backgroundColor: Grey[50],
       borderRadius: 2.0,
       boxShadow: shadows[level]));
-    watchPerformance(controller.performance);
+    watch(controller.performance);
   }
 
-  PopupMenuController controller;
-  List<PopupMenuItem> items;
-  int level;
-
   void syncFields(PopupMenu source) {
     controller = source.controller;
     items = source.items;

sdk/lib/widgets/scrollable.dart

@@ -30,13 +30,15 @@ abstract class Scrollable extends StatefulComponent {
     String key,
     this.backgroundColor,
     this.direction: ScrollDirection.vertical
-  }) : super(key: key) {
-    _animation = new AnimatedSimulation(_tickScrollOffset);
-  }
+  }) : super(key: key);
 
   Color backgroundColor;
   ScrollDirection direction;
 
+  void initState() {
+    _animation = new AnimatedSimulation(_tickScrollOffset);
+  }
+
   void syncFields(Scrollable source) {
     backgroundColor = source.backgroundColor;
     direction == source.direction;

sdk/lib/widgets/toggleable.dart

@@ -19,14 +19,7 @@ abstract class Toggleable extends AnimatedComponent {
     String key,
     this.value,
     this.onChanged
-  }) : super(key: key) {
-    _position = new AnimatedType<double>(0.0, end: 1.0);
-    _performance = new AnimationPerformance()
-      ..variable = position
-      ..duration = _kCheckDuration
-      ..progress = value ? 1.0 : 0.0;
-    watchPerformance(performance);
-  }
+  }) : super(key: key);
 
   bool value;
   ValueChanged onChanged;
@@ -37,6 +30,15 @@ abstract class Toggleable extends AnimatedComponent {
   AnimationPerformance _performance;
   AnimationPerformance get performance => _performance;
 
+  void initState() {
+    _position = new AnimatedType<double>(0.0, end: 1.0);
+    _performance = new AnimationPerformance()
+      ..variable = position
+      ..duration = _kCheckDuration
+      ..progress = value ? 1.0 : 0.0;
+    watch(performance);
+  }
+
   void syncFields(Toggleable source) {
     onChanged = source.onChanged;
     if (value != source.value) {