[m114] Suppress MultithreadTests.Device_Dropped*OnAnotherThread

These tests seem to cause flakiness in other sampling tests on NVIDIA.

(cherry picked from commit 759238b96202d09f6a8a9173f34417a356c89a8d)

Bug: dawn:1779
Bug: chromium:1444145
Change-Id: Ide341033a4f13d8294021752ad3d18850a7369d6
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/139960
Commit-Queue: Quyen Le <lehoangquyen@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Kokoro: Austin Eng <enga@chromium.org>
diff --git a/src/dawn/tests/end2end/MultithreadTests.cpp b/src/dawn/tests/end2end/MultithreadTests.cpp
index 6528660..22f3ce4 100644
--- a/src/dawn/tests/end2end/MultithreadTests.cpp
+++ b/src/dawn/tests/end2end/MultithreadTests.cpp
@@ -101,6 +101,10 @@
 
 // Test that dropping a device's last ref on another thread won't crash Instance::ProcessEvents.
 TEST_P(MultithreadTests, Device_DroppedOnAnotherThread) {
+    // TODO(crbug.com/dawn/1779): This test seems to cause flakiness in other sampling tests on
+    // NVIDIA.
+    DAWN_SUPPRESS_TEST_IF(IsD3D12() && IsNvidia());
+
     std::vector<wgpu::Device> devices(5);
 
     // Create devices.
@@ -132,6 +136,10 @@
 // Test that dropping a device's last ref inside a callback on another thread won't crash
 // Instance::ProcessEvents.
 TEST_P(MultithreadTests, Device_DroppedInCallback_OnAnotherThread) {
+    // TODO(crbug.com/dawn/1779): This test seems to cause flakiness in other sampling tests on
+    // NVIDIA.
+    DAWN_SUPPRESS_TEST_IF(IsD3D12() && IsNvidia());
+
     std::vector<wgpu::Device> devices(10);
 
     // Create devices.