[ADF-711] Drag and drop doesn't have the acceptedFilesType property (#3104)

* Added acceptedFilesType property for upload-drag-area component.
* Only those files will be uploaded which are included in acceptedFilesType.

lib/content-services/upload/components/upload-button.component.ts

@@ -41,6 +41,7 @@ import { Observable } from 'rxjs/Observable';
 import { Subject } from 'rxjs/Subject';
 import { PermissionModel } from '../../document-list/models/permissions.model';
 import 'rxjs/add/observable/throw';
+import { UploadBase } from './base-upload/upload-base';
 
 @Component({
     selector: 'adf-upload-button',
@@ -51,7 +52,7 @@ import 'rxjs/add/observable/throw';
     ],
     encapsulation: ViewEncapsulation.None
 })
-export class UploadButtonComponent implements OnInit, OnChanges, NodePermissionSubject {
+export class UploadButtonComponent extends UploadBase implements OnInit, OnChanges, NodePermissionSubject {
 
     /** Toggles component disabled state (if there is no node permission checking). */
     @Input()
@@ -69,10 +70,6 @@ export class UploadButtonComponent implements OnInit, OnChanges, NodePermissionS
     @Input()
     versioning: boolean = false;
 
-    /** List of allowed file extensions, for example: ".jpg,.gif,.png,.svg". */
-    @Input()
-    acceptedFilesType: string = '*';
-
     /** Sets a limit on the maximum size (in bytes) of a file to be uploaded.
      * Has no effect if undefined.
      */
@@ -118,6 +115,7 @@ export class UploadButtonComponent implements OnInit, OnChanges, NodePermissionS
                 protected translateService: TranslationService,
                 protected logService: LogService
             ) {
+                super();
     }
 
     ngOnInit() {
@@ -190,27 +188,6 @@ export class UploadButtonComponent implements OnInit, OnChanges, NodePermissionS
         });
     }
 
-    /**
-     * Checks if the given file is allowed by the extension filters
-     *
-     * @param file FileModel
-     */
-    protected isFileAcceptable(file: FileModel): boolean {
-        if (this.acceptedFilesType === '*') {
-            return true;
-        }
-
-        const allowedExtensions = this.acceptedFilesType
-            .split(',')
-            .map(ext => ext.replace(/^\./, ''));
-
-        if (allowedExtensions.indexOf(file.extension) !== -1) {
-            return true;
-        }
-
-        return false;
-    }
-
     /**
      * Checks if the given file is an acceptable size
      *