Descriptorize ShaderModule

Change-Id: Ic79d00380f583485de0fb05bd47b1f869919ebe6
diff --git a/src/dawn_native/metal/ShaderModuleMTL.h b/src/dawn_native/metal/ShaderModuleMTL.h
index 60ed58f..a021e42 100644
--- a/src/dawn_native/metal/ShaderModuleMTL.h
+++ b/src/dawn_native/metal/ShaderModuleMTL.h
@@ -25,11 +25,12 @@
 
 namespace dawn_native { namespace metal {
 
+    class Device;
     class PipelineLayout;
 
     class ShaderModule : public ShaderModuleBase {
       public:
-        ShaderModule(ShaderModuleBuilder* builder);
+        ShaderModule(Device* device, const ShaderModuleDescriptor* descriptor);
 
         struct MetalFunctionData {
             id<MTLFunction> function;