Don't consider member function defs when rewriting aliases

Previously, the compiler would crash when emitting member function names that
refer to collapsed properties. This is a problem when the output language is
ES6 and above.

PiperOrigin-RevId: 553475247

Author: sjamesr

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

@@ -975,6 +975,12 @@ private void rewriteNestedAliasReference(
           continue;
         }
 
+        if (target.isMemberFunctionDef()) {
+          // In the case of a method reference, the reference to the alias is not fully qualified,
+          // so we should not touch it, see b/293184904.
+          continue;
+        }
+
         for (int i = 0; i <= depth; i++) {
           if (target.isGetProp()) {
             target = target.getFirstChild();

test/com/google/javascript/jscomp/integration/IntegrationTest.java

@@ -4797,4 +4797,43 @@ public void testNoSideEffectsPropagationOnStaticMembers_withEs2018Out() {
         // to hide side-effects.
         "");
   }
+
+  @Test
+  public void testDeclareLegacyNamespaceSubModuleCrash() {
+    CompilerOptions options = createCompilerOptions();
+    CompilationLevel.ADVANCED_OPTIMIZATIONS.setOptionsForCompilationLevel(options);
+    options.setLanguageOut(LanguageMode.ECMASCRIPT_2016);
+
+    options.setRemoveDeadCode(false);
+    options.setRemoveUnusedVariables(Reach.NONE);
+    options.setRemoveUnusedClassProperties(false);
+
+    // Ensures that references to aliases that occur within member function defs do not crash the
+    // compiler (see b/293184904). In this example, the name 'method' in 'static method() {...}'
+    // is a reference to a.b.Foo.method, but since the reference is not fully qualified, the
+    // compiler should not try to touch it.
+    //
+    // This test case contains a use of a computed property to ensure that the fix for the above
+    // problem does not affect computed properties.
+    test(
+        options,
+        new String[] {
+          lines(
+              "goog.module('a.b');",
+              "goog.module.declareLegacyNamespace();",
+              "var b = {};",
+              "exports = b;\n"),
+          lines(
+              "goog.provide('a.b.Foo');",
+              "a.b.Foo = class {",
+              "  static method() {}",
+              "  static getVarName() { return 'someVar'; }",
+              "};",
+              "var x = {[a.b.Foo.getVarName()]: '4'};",
+              "alert(x['someVar']);")
+        },
+        new String[] {
+          lines(""), lines("alert(\"4\");"),
+        });
+  }
 }