Use isInClosureUnawareSubtree instead of isClosureUnawareCode for AstValidator

This effectively runs AstValidator feature validation more often: now we can run it over code in a /** @closureUnaware @fileoverview */ script, that is not itself in a @closureUnaware function.

PiperOrigin-RevId: 845305613

Author: lauraharker

src/com/google/javascript/jscomp/AstValidator.java

@@ -2125,7 +2125,7 @@ private void validateMaximumChildCount(Node n, int i) {
   }
 
   private void validateFeature(Feature feature, Node n) {
-    if (n.isClosureUnawareCode()) {
+    if (n.getIsInClosureUnawareSubtree()) {
       // Closure-unaware code is currently hidden from transpilation passes in the compiler, so it
       // might still contain features that should have been transpiled.
       // TODO: b/321233583 - Once JSCompiler can transpile closure-unaware code, remove this