sheriff: mark InputHandlerProxyEventQueueTest disabled under sanitizers

This test is flaky under asan & tsan.

Bug: 1029250
Change-Id: I9fd12f89cafdd0d01de1b59941f7d0bf07212c1a
Tbr: bokan@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1972503Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#725975}

ui/events/blink/input_handler_proxy_unittest.cc

@@ -1600,7 +1600,18 @@ TEST_F(InputHandlerProxyEventQueueTest, VSyncAlignedGestureScroll) {
   testing::Mock::VerifyAndClearExpectations(&mock_input_handler_);
 }
 
-TEST_F(InputHandlerProxyEventQueueTest, VSyncAlignedGestureScrollPinchScroll) {
+#if defined(ADDRESS_SANITIZER) || defined(THREAD_SANITIZER)
+// Flaky under sanitizers and in other "slow" bot configs:
+// https://crbug.com/1029250
+#define MAYBE_VSyncAlignedGestureScrollPinchScroll \
+  DISABLED_VSyncAlignedGestureScrollPinchScroll
+#else
+#define MAYBE_VSyncAlignedGestureScrollPinchScroll \
+  VSyncAlignedGestureScrollPinchScroll
+#endif
+
+TEST_F(InputHandlerProxyEventQueueTest,
+       MAYBE_VSyncAlignedGestureScrollPinchScroll) {
   // Handle scroll on compositor.
   cc::InputHandlerScrollResult scroll_result_did_scroll_;
   scroll_result_did_scroll_.did_scroll = true;