simplifications inspired by review

Author: erik-krogh

javascript/ql/lib/semmle/javascript/ApiGraphs.qll

@@ -210,12 +210,7 @@ module API {
      * This is similar to `asSink()` but additionally includes nodes that transitively reach a sink by data flow.
      * See `asSink()` for examples.
      */
-    DataFlow::Node getAValueReachingSink() {
-      result = Impl::trackDefNode(this.asSink())
-      or
-      // in case `asSink()` is not a `SourceNode`.
-      result = this.asSink()
-    }
+    DataFlow::Node getAValueReachingSink() { result = Impl::trackDefNode(this.asSink()) }
 
     /** DEPRECATED. This predicate has been renamed to `asSink`. */
     deprecated DataFlow::Node getARhs() { result = this.asSink() }

javascript/ql/lib/semmle/javascript/security/dataflow/UnsafeShellCommandConstructionCustomizations.qll

@@ -169,7 +169,7 @@ module UnsafeShellCommandConstruction {
     or
     exists(API::Node node |
       node.asSink() = sys.getOptionsArg() and
-      node.getMember("shell").getAValueReachingSink().mayHaveBooleanValue(true)
+      node.getMember("shell").asSink().mayHaveBooleanValue(true)
     )
   }