Fix DawnTest HasToggleEnabled referencing the wrong device

It should reference the backendDevice as the |device| points to
the wire client device when the wire is used.

Bug: none
Change-Id: Iac6399df96ea0226d8b9ba8f6196185e43c41adb
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/34923
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>
diff --git a/src/tests/DawnTest.cpp b/src/tests/DawnTest.cpp
index 2e3532c..4de63a5 100644
--- a/src/tests/DawnTest.cpp
+++ b/src/tests/DawnTest.cpp
@@ -709,7 +709,7 @@
 }
 
 bool DawnTestBase::HasToggleEnabled(const char* toggle) const {
-    auto toggles = dawn_native::GetTogglesUsed(device.Get());
+    auto toggles = dawn_native::GetTogglesUsed(backendDevice);
     return std::find_if(toggles.begin(), toggles.end(), [toggle](const char* name) {
                return strcmp(toggle, name) == 0;
            }) != toggles.end();