fix(chips): filter's click.preventDefault() not working when also updating selected

Fixes #5199

This bug appeared when calling prevent default as well as changing the state of the chip in the same listener. Now calling preventDefault will always revert to the previous value.

PiperOrigin-RevId: 595199149

chips/internal/filter-chip.ts

@@ -108,11 +108,17 @@ export class FilterChip extends MultiActionChip {
       return;
     }
 
+    // Store prevValue to revert in case `chip.selected` is changed during an
+    // event listener.
+    const prevValue = this.selected;
     this.selected = !this.selected;
 
     const preventDefault = !redispatchEvent(this, event);
     if (preventDefault) {
-      this.selected = !this.selected;
+      // We should not do `this.selected = !this.selected`, since a client
+      // click listener could change its value. Instead, always revert to the
+      // original value.
+      this.selected = prevValue;
       return;
     }
   }

chips/internal/filter-chip_test.ts

@@ -66,5 +66,38 @@ describe('Filter chip', () => {
       await harness.clickWithMouse();
       expect(handler).toHaveBeenCalledTimes(0);
     });
+
+    it('always reverts value on preventDefault() even if selected is changed in listener', async () => {
+      const {chip, harness} = await setupTest();
+
+      chip.addEventListener(
+        'click',
+        (event) => {
+          event.preventDefault();
+          chip.selected = false;
+        },
+        {once: true},
+      );
+
+      await harness.clickWithMouse();
+      expect(chip.selected)
+        .withContext('chip.selected reverts to false')
+        .toBeFalse();
+
+      chip.selected = true;
+      chip.addEventListener(
+        'click',
+        (event) => {
+          event.preventDefault();
+          chip.selected = false;
+        },
+        {once: true},
+      );
+
+      await harness.clickWithMouse();
+      expect(chip.selected)
+        .withContext('chip.selected reverts to true')
+        .toBeTrue();
+    });
   });
 });