file-dialog: apply the default filter

The commit fixes an issue where the `file-dialog` filter was not
respected when we display the dialog initially. Previously a change
event in the filter meant that the dialog was properly filtered.

Signed-off-by: vince-fugnitto <vincent.fugnitto@ericsson.com>

packages/filesystem/src/browser/file-dialog/file-dialog.ts

@@ -167,6 +167,10 @@ export abstract class FileDialog<T> extends AbstractDialog<T> {
 
         if (this.props.filters) {
             this.treeFiltersRenderer = this.treeFiltersFactory({ suppliedFilters: this.props.filters, fileDialogTree: this.widget.model.tree });
+            const filters = Object.keys(this.props.filters);
+            if (filters.length) {
+                this.widget.model.tree.setFilter(this.props.filters[filters[0]]);
+            }
         }
     }