Add test for SamplerDescriptor trivial frontend defaults.

Check that they work with the maxAnisotropy > 1 check.

Bug: dawn:2475
Change-Id: Id69cc7217c101f6abc669f64b53642bf192393ce
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/183281
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
diff --git a/src/dawn/tests/unittests/validation/SamplerValidationTests.cpp b/src/dawn/tests/unittests/validation/SamplerValidationTests.cpp
index 31a0384..8500718 100644
--- a/src/dawn/tests/unittests/validation/SamplerValidationTests.cpp
+++ b/src/dawn/tests/unittests/validation/SamplerValidationTests.cpp
@@ -134,4 +134,13 @@
     }
 }
 
+TEST_F(SamplerValidationTest, ValidFilterAnisotropicWithUndefined) {
+    wgpu::SamplerDescriptor kValidAnisoSamplerDesc = {};
+    kValidAnisoSamplerDesc.maxAnisotropy = 2;
+    kValidAnisoSamplerDesc.minFilter = wgpu::FilterMode::Undefined;
+    kValidAnisoSamplerDesc.magFilter = wgpu::FilterMode::Undefined;
+    kValidAnisoSamplerDesc.mipmapFilter = wgpu::MipmapFilterMode::Undefined;
+    { device.CreateSampler(); }
+}
+
 }  // anonymous namespace