Check ShaderModuleDescriptor->nextInChain

Change-Id: Iffa7485b3a2dc43911c86ac614e7d99d737aaf6f

src/dawn_native/ShaderModule.cpp

diff --git a/src/dawn_native/ShaderModule.cpp b/src/dawn_native/ShaderModule.cpp
index db7119c..699aa30 100644
--- a/src/dawn_native/ShaderModule.cpp
+++ b/src/dawn_native/ShaderModule.cpp
@@ -23,7 +23,8 @@
 
 namespace dawn_native {
 
-    MaybeError ValidateShaderModuleDescriptor(DeviceBase*, const ShaderModuleDescriptor*) {
+    MaybeError ValidateShaderModuleDescriptor(DeviceBase*, const ShaderModuleDescriptor* descriptor) {
+        DAWN_TRY_ASSERT(descriptor->nextInChain == nullptr, "nextInChain must be nullptr");
         // TODO(cwallez@chromium.org): Use spirv-val to check the module is well-formed
         return {};
     }