Fix RewriteClassMember to skip handling computed property when it is not in a class body.

PiperOrigin-RevId: 615559359

Author: Closure Team

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

@@ -96,9 +96,11 @@ public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
         classStack.peek().recordStaticBlock(n);
         break;
       case COMPUTED_PROP:
-        checkState(!classStack.isEmpty());
-        if (n.getParent().isClassMembers() && NodeUtil.canBeSideEffected(n.getFirstChild())) {
-          classStack.peek().computedPropMembers.add(n);
+        if (n.getParent().isClassMembers()) {
+          checkState(!classStack.isEmpty());
+          if (NodeUtil.canBeSideEffected(n.getFirstChild())) {
+            classStack.peek().computedPropMembers.add(n);
+          }
         }
         break;
       default:

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

@@ -896,6 +896,24 @@ public void testSideEffectsInComputedField() {
                 "    }",
                 "  }",
                 "}")));
+
+    rewriteFieldOrBlockTest(
+        srcs(
+            lines(
+                "x.a = 'b';",
+                "y = { [x.a]:'aa' };", // computed property not in a class body
+                "class Baz {",
+                "  z = 1;",
+                "}")),
+        expected(
+            lines(
+                "x.a = 'b';",
+                "y = {[x.a]:'aa'};",
+                "class Baz {",
+                "  constructor() {",
+                "    this.z = 1;",
+                "  }",
+                "}")));
   }
 
   @Test