Refactor test to account for animations.

Author: crisbeto

src/lib/dialog/dialog.spec.ts

@@ -163,7 +163,7 @@ describe('MdDialog', () => {
     })).toBe(ref);
   });
 
-  it('should notify the observers if all open dialogs have finished closing', () => {
+  it('should notify the observers if all open dialogs have finished closing', async(() => {
     const ref1 = dialog.open(PizzaMsg, {
       viewContainerRef: testViewContainerRef
     });
@@ -177,10 +177,19 @@ describe('MdDialog', () => {
     });
 
     ref1.close();
-    expect(allClosed).toBeFalsy();
-    ref2.close();
-    expect(allClosed).toBeTruthy();
-  });
+    viewContainerFixture.detectChanges();
+
+    viewContainerFixture.whenStable().then(() => {
+      expect(allClosed).toBeFalsy();
+
+      ref2.close();
+      viewContainerFixture.detectChanges();
+
+      viewContainerFixture.whenStable().then(() => {
+        expect(allClosed).toBeTruthy();
+      });
+    });
+  }));
 
   it('should should override the width of the overlay pane', () => {
     dialog.open(PizzaMsg, {