fix(bottom-sheet): bottom-sheet content not being read out by screen readers

src/lib/bottom-sheet/bottom-sheet-config.ts

@@ -47,8 +47,11 @@ export class MatBottomSheetConfig<D = any> {
    */
   closeOnNavigation?: boolean = true;
 
+  // Note that this is disabled by default, because while the a11y recommendations are to focus
+  // the first focusable element, doing so prevents screen readers from reading out the
+  // rest of the bottom sheet content.
   /** Whether the bottom sheet should focus the first focusable element on open. */
-  autoFocus?: boolean = true;
+  autoFocus?: boolean = false;
 
   /**
    * Whether the bottom sheet should restore focus to the

src/lib/bottom-sheet/bottom-sheet.spec.ts

@@ -514,18 +514,32 @@ describe('MatBottomSheet', () => {
     beforeEach(() => document.body.appendChild(overlayContainerElement));
     afterEach(() => document.body.removeChild(overlayContainerElement));
 
-    it('should focus the first tabbable element of the bottom sheet on open', fakeAsync(() => {
+    it('should focus the bottom sheet container by default', fakeAsync(() => {
       bottomSheet.open(PizzaMsg, {
-        viewContainerRef: testViewContainerRef
+        viewContainerRef: testViewContainerRef,
       });
 
       viewContainerFixture.detectChanges();
       flushMicrotasks();
 
-      expect(document.activeElement!.tagName)
-          .toBe('INPUT', 'Expected first tabbable element (input) in the sheet to be focused.');
+      expect(document.activeElement!.tagName).toBe('MAT-BOTTOM-SHEET-CONTAINER',
+          'Expected bottom sheet container to be focused.');
     }));
 
+    it('should focus the first tabbable element of the bottom sheet on open when' +
+      'autoFocus is enabled', fakeAsync(() => {
+        bottomSheet.open(PizzaMsg, {
+          viewContainerRef: testViewContainerRef,
+          autoFocus: true
+        });
+
+        viewContainerFixture.detectChanges();
+        flushMicrotasks();
+
+        expect(document.activeElement!.tagName).toBe('INPUT',
+            'Expected first tabbable element (input) in the sheet to be focused.');
+      }));
+
     it('should allow disabling focus of the first tabbable element', fakeAsync(() => {
       bottomSheet.open(PizzaMsg, {
         viewContainerRef: testViewContainerRef,