fix(Schedulers): Fix issue where canceling an asap or animationFrame action early could throw (#2638)

Author: trxcllnt

spec/schedulers/AnimationFrameScheduler-spec.ts

@@ -25,6 +25,21 @@ describe('Scheduler.animationFrame', () => {
     sandbox.restore();
   });
 
+  it('should cancel animationFrame actions when delay > 0', () => {
+    let actionHappened = false;
+    const sandbox = sinon.sandbox.create();
+    const fakeTimer = sandbox.useFakeTimers();
+    animationFrame.schedule(() => {
+      actionHappened = true;
+    }, 50).unsubscribe();
+    expect(actionHappened).to.be.false;
+    fakeTimer.tick(25);
+    expect(actionHappened).to.be.false;
+    fakeTimer.tick(25);
+    expect(actionHappened).to.be.false;
+    sandbox.restore();
+  });
+
   it('should schedule an action to happen later', (done: MochaDone) => {
     let actionHappened = false;
     animationFrame.schedule(() => {

spec/schedulers/AsapScheduler-spec.ts

@@ -25,6 +25,21 @@ describe('Scheduler.asap', () => {
     sandbox.restore();
   });
 
+  it('should cancel asap actions when delay > 0', () => {
+    let actionHappened = false;
+    const sandbox = sinon.sandbox.create();
+    const fakeTimer = sandbox.useFakeTimers();
+    asap.schedule(() => {
+      actionHappened = true;
+    }, 50).unsubscribe();
+    expect(actionHappened).to.be.false;
+    fakeTimer.tick(25);
+    expect(actionHappened).to.be.false;
+    fakeTimer.tick(25);
+    expect(actionHappened).to.be.false;
+    sandbox.restore();
+  });
+
   it('should schedule an action to happen later', (done: MochaDone) => {
     let actionHappened = false;
     asap.schedule(() => {

src/scheduler/AsyncAction.ts

@@ -137,7 +137,6 @@ export class AsyncAction<T> extends Action<T> {
     const index = actions.indexOf(this);
 
     this.work  = null;
-    this.delay = null;
     this.state = null;
     this.pending = false;
     this.scheduler = null;
@@ -149,5 +148,7 @@ export class AsyncAction<T> extends Action<T> {
     if (id != null) {
       this.id = this.recycleAsyncId(scheduler, id, null);
     }
+
+    this.delay = null;
   }
 }