fix(datepicker): md-open-on-focus constantly re-opens on close w/ IE11 (#11440)

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- [x] The commit message follows [our guidelines](https://github.com/angular/material/blob/master/.github/CONTRIBUTING.md#-commit-message-format)
- [ ] Tests for the changes have been added or this is not a bug fix / enhancement
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## PR Type
What kind of change does this PR introduce?
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[x] Bugfix
[ ] Enhancement
[ ] Documentation content changes
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
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## What is the current behavior?
- md-open-on-focus constantly re-opens on close w/ IE11
    - we don't want `$mdUtil.nextTick`'s batching features in this case
        - especially on a low performance or heavily loaded device

<!-- Please describe the current behavior that you are modifying and link to one or more relevant issues. -->
Issue Number: 
Fixes #10999

## What is the new behavior?
- Use `$timeout` instead of  `$mdUtil.nextTick`.
    - Datepicker is no longer re-opened constantly when closed on IE11.

## Does this PR introduce a breaking change?
```
[ ] Yes
[x] No
```
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## Other information

Author: Splaktar

src/components/datepicker/js/datepickerDirective.js

@@ -252,8 +252,8 @@
    *
    * @ngInject @constructor
    */
-  function DatePickerCtrl($scope, $element, $attrs, $window, $mdConstant,
-    $mdTheming, $mdUtil, $mdDateLocale, $$mdDateUtil, $$rAF, $filter) {
+  function DatePickerCtrl($scope, $element, $attrs, $window, $mdConstant, $mdTheming, $mdUtil,
+                          $mdDateLocale, $$mdDateUtil, $$rAF, $filter, $timeout) {
 
     /** @final */
     this.$window = $window;
@@ -264,7 +264,7 @@
     /** @final */
     this.$mdConstant = $mdConstant;
 
-    /* @final */
+    /** @final */
     this.$mdUtil = $mdUtil;
 
     /** @final */
@@ -273,6 +273,9 @@
     /** @final */
     this.$mdDateLocale = $mdDateLocale;
 
+    /** @final */
+    this.$timeout = $timeout;
+
     /**
      * The root document element. This is used for attaching a top-level click handler to
      * close the calendar panel when a click outside said panel occurs. We use `documentElement`
@@ -833,7 +836,7 @@
         // in IE when md-open-on-focus is set. Also it needs to trigger
         // a digest, in order to prevent issues where the calendar wasn't
         // showing up on the next open.
-        self.$mdUtil.nextTick(reset);
+        self.$timeout(reset);
       } else {
         reset();
       }