Small tweaks to SSR to match #14594 (#14618)

* Small tweaks to SSR to match #14594

* Remove unnecessary comparison

Author: gaearon

Diff for: src/ReactShallowRenderer.js

@@ -303,7 +303,7 @@ class ReactShallowRenderer {
       this._validateCurrentlyRenderingComponent();
       this._createWorkInProgressHook();
 
-      const nextDeps = deps !== undefined && deps !== null ? deps : null;
+      const nextDeps = deps !== undefined ? deps : null;
 
       if (
         this._workInProgressHook !== null &&