fix: replace extendObject utility w/ object spread

BREAKING CHANGE: The `extendObject` utility function is removed.

Author: jelbourn

src/lib/core/datetime/native-date-adapter.ts

@@ -8,7 +8,6 @@
 
 import {Inject, Injectable, Optional} from '@angular/core';
 import {DateAdapter, MAT_DATE_LOCALE} from './date-adapter';
-import {extendObject} from '../util/object-extend';
 
 // TODO(mmalerba): Remove when we no longer support safari 9.
 /** Whether the browser supports the Intl API. */
@@ -179,7 +178,7 @@ export class NativeDateAdapter extends DateAdapter<Date> {
         date = new Date(Date.UTC(
             date.getFullYear(), date.getMonth(), date.getDate(), date.getHours(),
             date.getMinutes(), date.getSeconds(), date.getMilliseconds()));
-        displayFormat = extendObject({}, displayFormat, {timeZone: 'utc'});
+        displayFormat = {...displayFormat, timeZone: 'utc'};
       }
       let dtf = new Intl.DateTimeFormat(this.locale, displayFormat);
       return this._stripDirectionalityCharacters(dtf.format(date));

src/lib/core/public_api.ts

@@ -20,7 +20,6 @@ export * from './placeholder/placeholder-options';
 export * from './ripple/index';
 export * from './selection/index';
 export * from './style/index';
-export * from './util/object-extend';
 export * from './mat-exports';
 
 // TODO: don't have this

src/lib/core/util/object-extend.spec.ts

@@ -27,7 +27,6 @@ import {
   SkipSelf,
   TemplateRef,
 } from '@angular/core';
-import {extendObject} from '@angular/material/core';
 import {Observable} from 'rxjs/Observable';
 import {defer} from 'rxjs/observable/defer';
 import {Subject} from 'rxjs/Subject';
@@ -319,5 +318,5 @@ export class MdDialog {
  * @returns The new configuration object.
  */
 function _applyConfigDefaults(config?: MdDialogConfig): MdDialogConfig {
-  return extendObject(new MdDialogConfig(), config);
+  return {...new MdDialogConfig(), ...config};
 }

src/lib/core/util/object-extend.ts

@@ -10,7 +10,6 @@ import {LiveAnnouncer} from '@angular/cdk/a11y';
 import {Overlay, OverlayConfig, OverlayRef} from '@angular/cdk/overlay';
 import {ComponentPortal, ComponentType, PortalInjector} from '@angular/cdk/portal';
 import {ComponentRef, Injectable, Injector, Optional, SkipSelf} from '@angular/core';
-import {extendObject} from '@angular/material/core';
 import {SimpleSnackBar} from './simple-snack-bar';
 import {MD_SNACK_BAR_DATA, MdSnackBarConfig} from './snack-bar-config';
 import {MdSnackBarContainer} from './snack-bar-container';
@@ -206,5 +205,5 @@ export class MdSnackBar {
  * @returns The new configuration object with defaults applied.
  */
 function _applyConfigDefaults(config?: MdSnackBarConfig): MdSnackBarConfig {
-  return extendObject(new MdSnackBarConfig(), config);
+  return {...new MdSnackBarConfig(), ...config};
 }