a === b -> identical(a, b)

samples/swarm/swarm_ui_lib/touch/Momentum.dart

Index: samples/swarm/swarm_ui_lib/touch/Momentum.dart
diff --git a/samples/swarm/swarm_ui_lib/touch/Momentum.dart b/samples/swarm/swarm_ui_lib/touch/Momentum.dart
index 269b722e5b4f4a34eea6a36cc04aa2a3f8b9131f..034c025399ef74b42470c2c1a2660cce519c819f 100644
--- a/samples/swarm/swarm_ui_lib/touch/Momentum.dart
+++ b/samples/swarm/swarm_ui_lib/touch/Momentum.dart
@@ -278,11 +278,11 @@ class SingleDimensionPhysics {
     velocity = v * _MS_PER_FRAME * _INITIAL_VELOCITY_BOOST_FACTOR;
 
     if (velocity.abs() < _MIN_VELOCITY) {
-      if (_minCoord !== null && _currentOffset < _minCoord) {
+      if (_minCoord != null && _currentOffset < _minCoord) {
         velocity = (_minCoord - _currentOffset) * _POST_BOUNCE_COEFFICIENT;
         velocity = Math.max(velocity, _MIN_STEP_VELOCITY);
         _bouncingState = BouncingState.BOUNCING_BACK;
-      } else if (_maxCoord !== null && _currentOffset > _maxCoord) {
+      } else if (_maxCoord != null && _currentOffset > _maxCoord) {
         velocity = (_currentOffset - _maxCoord) * _POST_BOUNCE_COEFFICIENT;
         velocity = -Math.max(velocity, _MIN_STEP_VELOCITY);
         _bouncingState = BouncingState.BOUNCING_BACK;
@@ -306,10 +306,10 @@ class SingleDimensionPhysics {
     }
 
     num stretchDistance;
-    if (_minCoord !== null && _currentOffset < _minCoord) {
+    if (_minCoord != null && _currentOffset < _minCoord) {
       stretchDistance = _minCoord - _currentOffset;
     } else {
-      if (_maxCoord !== null && _currentOffset > _maxCoord) {
+      if (_maxCoord != null && _currentOffset > _maxCoord) {
         stretchDistance = _maxCoord - _currentOffset;
       }
     }
@@ -334,7 +334,7 @@ class SingleDimensionPhysics {
   void step() {
     // It is common for scrolling to be disabled so in these cases we want to
     // avoid needless calculations.
-    if (velocity !== null) {
+    if (velocity != null) {
       _currentOffset += velocity;
       _adjustVelocity();
     }
@@ -436,16 +436,16 @@ class TimeoutMomentum implements Momentum {
   bool start(Coordinate velocity, Coordinate minCoord, Coordinate maxCoord,
              Coordinate initialOffset, [num decelerationFactor = null]) {
     _customDecelerationFactor = _defaultDecelerationFactor;
-    if (decelerationFactor !== null) {
+    if (decelerationFactor != null) {
       _customDecelerationFactor = decelerationFactor;
     }
 
-    if (_stepTimeout !== null) {
+    if (_stepTimeout != null) {
       Env.cancelRequestAnimationFrame(_stepTimeout);
       _stepTimeout = null;
     }
 
-    assert (_stepTimeout === null);
+    assert (_stepTimeout == null);
     assert(minCoord.x <= maxCoord.x);
     assert(minCoord.y <= maxCoord.y);
     _previousOffset = initialOffset.clone();
@@ -490,7 +490,7 @@ class TimeoutMomentum implements Momentum {
     // Prune moves that are more than 1 frame behind when we have more
     // available moves.
     num lastEpoch = timestamp - SingleDimensionPhysics._MS_PER_FRAME;
-    while (!_moves.isEmpty && _moves.first !== _moves.last
+    while (!_moves.isEmpty && !identical(_moves.first, _moves.last)
         && _moves.first.time < lastEpoch) {
       _moves.removeFirst();
     }
@@ -500,7 +500,7 @@ class TimeoutMomentum implements Momentum {
       _delegate.onDecelerate(move.x, move.y);
       if (!_moves.isEmpty) {
         num nextTime = _moves.first.time;
-        assert(_stepTimeout === null);
+        assert(_stepTimeout == null);
         _stepTimeout = Env.requestAnimationFrame(_step, null, nextTime);
       } else {
         stop();
@@ -511,7 +511,7 @@ class TimeoutMomentum implements Momentum {
   void abort() {
     _decelerating = false;
     _moves.clear();
-    if (_stepTimeout !== null) {
+    if (_stepTimeout != null) {
       Env.cancelRequestAnimationFrame(_stepTimeout);
       _stepTimeout = null;
     }
@@ -533,7 +533,7 @@ class TimeoutMomentum implements Momentum {
       velocity = new Coordinate(0, 0);
     }
     _moves.clear();
-    if (_stepTimeout !== null) {
+    if (_stepTimeout != null) {
       Env.cancelRequestAnimationFrame(_stepTimeout);
       _stepTimeout = null;
     }