support export default of anonymous functions and classes (#1954)

lib/parse.js

@@ -2373,10 +2373,7 @@ function parse($TEXT, options) {
             }
         }
 
-        var is_definition =
-            is("keyword", "var") || is("keyword", "let") || is("keyword", "const") ||
-            is("keyword", "class") || is("keyword", "function");
-
+        var is_definition = is("keyword", "var") || is("keyword", "let") || is("keyword", "const");
         if (is_definition) {
             exported_definition = statement();
         } else {

test/compress/harmony.js

@@ -241,6 +241,30 @@ export_default_array: {
     expect_exact: "export default[3,foo];"
 }
 
+export_default_anon_function: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        export default function(){
+            console.log(1 + 2);
+        }
+    }
+    expect_exact: "export default function(){console.log(3)};"
+}
+
+export_default_anon_class: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        export default class {
+            foo() { console.log(1 + 2); }
+        }
+    }
+    expect_exact: "export default class{foo(){console.log(3)}};"
+}
+
 export_module_statement: {
     input: {
         export * from "a.js";