Fix RewriteClassMember modifying computed property in an object literal.

PiperOrigin-RevId: 615209502

Author: Closure Team

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

@@ -97,7 +97,7 @@ public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
         break;
       case COMPUTED_PROP:
         checkState(!classStack.isEmpty());
-        if (NodeUtil.canBeSideEffected(n.getFirstChild())) {
+        if (n.getParent().isClassMembers() && NodeUtil.canBeSideEffected(n.getFirstChild())) {
           classStack.peek().computedPropMembers.add(n);
         }
         break;

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

@@ -870,6 +870,32 @@ public void testSideEffectsInComputedField() {
                 "}",
                 "Baz.x = Baz.STATIC$FIELD$5$x();",
                 "Baz[COMPFIELD$2] = Baz.STATIC$FIELD$6();")));
+
+    rewriteFieldOrBlockTest(
+        srcs(
+            lines(
+                "class Baz {",
+                "  z = 1;",
+                "  func(x) {",
+                "    x.a = 'y';",
+                "    return {",
+                "      [x.a]:'aa'", // computed property in an object literal remains unchanged
+                "    }",
+                "  }",
+                "}")),
+        expected(
+            lines(
+                "class Baz {",
+                "  constructor() {",
+                "    this.z = 1;",
+                "  }",
+                "  func(x) {",
+                "    x.a = 'y';",
+                "    return {",
+                "      [x.a]:'aa'",
+                "    }",
+                "  }",
+                "}")));
   }
 
   @Test