fix(datepicker): add role to date range input

Adds a `group` role to the date range input since it groups two inputs.

Author: crisbeto

src/material/datepicker/date-range-input.spec.ts

@@ -89,6 +89,13 @@ describe('MatDateRangeInput', () => {
     expect(fixture.componentInstance.end.nativeElement.getAttribute('type')).toBe('text');
   });
 
+  it('should set the correct role on the range input', () => {
+    const fixture = createComponent(StandardRangePicker);
+    fixture.detectChanges();
+    const rangeInput = fixture.nativeElement.querySelector('.mat-date-range-input');
+    expect(rangeInput.getAttribute('role')).toBe('group');
+  });
+
   it('should mark the entire range input as disabled if both inputs are disabled', () => {
     const fixture = createComponent(StandardRangePicker);
     fixture.detectChanges();

src/material/datepicker/date-range-input.ts

@@ -47,6 +47,7 @@ let nextUniqueId = 0;
     'class': 'mat-date-range-input',
     '[class.mat-date-range-input-hide-placeholders]': '_shouldHidePlaceholders()',
     '[attr.id]': 'null',
+    'role': 'group',
   },
   changeDetection: ChangeDetectionStrategy.OnPush,
   encapsulation: ViewEncapsulation.None,