Add a test to ensure eval?.() transpiles to indirect eval

This behavior is required by the ECMAScript spec.

PiperOrigin-RevId: 322468581

Author: brad4d

test/com/google/javascript/jscomp/RewriteOptionalChainingOperatorTest.java

@@ -91,6 +91,18 @@ public static class BaseTestClass extends CompilerTestCase {
     public static final ImmutableList<Object> cases() {
       return ImmutableList.copyOf(
           new Object[][] {
+            {
+              "eval?.('foo()');",
+              lines(
+                  "let tmp0;", //
+                  "(tmp0 = eval) == null",
+                  "    ? void 0",
+                  // The spec says that `eval?.()` must behave like an indirect
+                  // eval, so it is important that `eval?.()` not be transpiled to
+                  // anything that ends up containing `eval()`.
+                  // We must be sure to call it using the temporary variable.
+                  "    : tmp0('foo()');")
+            },
             {
               "obj?.ary[getNum()].obj.obj?.obj.ary",
               lines(