fix(cdk/table): set default role of table to 'table'

Author: annieyw

src/cdk/table/cell.ts

@@ -178,7 +178,7 @@ export class CdkHeaderCell extends BaseCdkCell {
   selector: 'cdk-footer-cell, td[cdk-footer-cell]',
   host: {
     'class': 'cdk-footer-cell',
-    'role': 'gridcell',
+    'role': 'cell',
   },
 })
 export class CdkFooterCell extends BaseCdkCell {
@@ -192,7 +192,7 @@ export class CdkFooterCell extends BaseCdkCell {
   selector: 'cdk-cell, td[cdk-cell]',
   host: {
     'class': 'cdk-cell',
-    'role': 'gridcell',
+    'role': 'cell',
   },
 })
 export class CdkCell extends BaseCdkCell {

src/cdk/table/table.ts

@@ -512,7 +512,7 @@ export class CdkTable<T> implements AfterContentChecked, CollectionViewer, OnDes
       @Optional() @SkipSelf() @Inject(STICKY_POSITIONING_LISTENER)
         protected readonly _stickyPositioningListener: StickyPositioningListener) {
     if (!role) {
-      this._elementRef.nativeElement.setAttribute('role', 'grid');
+      this._elementRef.nativeElement.setAttribute('role', 'table');
     }
 
     this._document = _document;

src/material-experimental/mdc-table/cell.ts

@@ -93,7 +93,6 @@ export class MatHeaderCell extends CdkHeaderCell {}
   selector: 'mat-footer-cell, td[mat-footer-cell]',
   host: {
     'class': 'mat-mdc-footer-cell mdc-data-table__cell',
-    'role': 'gridcell',
   },
 })
 export class MatFooterCell extends CdkFooterCell {}
@@ -103,7 +102,6 @@ export class MatFooterCell extends CdkFooterCell {}
   selector: 'mat-cell, td[mat-cell]',
   host: {
     'class': 'mat-mdc-cell mdc-data-table__cell',
-    'role': 'gridcell',
   },
 })
 export class MatCell extends CdkCell {}