Enables device.destroy API now that CTS tests have been implemented.

Bug: dawn:628
Change-Id: I52e9c2d04c605b64a5fd80762891fc44e2c2c53a
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/84921
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Loko Kung <lokokung@google.com>

src/dawn/native/Device.cpp

@@ -412,12 +412,6 @@ namespace dawn::native {
     }
 
     void DeviceBase::APIDestroy() {
-        // TODO(crbug.com/dawn/628) Re-enable once CTS testing is in place and passing.
-        if (IsToggleEnabled(Toggle::DisallowUnsafeAPIs)) {
-            ConsumedError(DAWN_VALIDATION_ERROR(
-                "Explicit device.destroy() is disallowed because it is not fully implemented"));
-            return;
-        }
         Destroy();
     }