[modules] Refactor parsing of anonymous declarations in default exports.

BUG=

Review-Url: https://codereview.chromium.org/2111153002
Cr-Commit-Position: refs/heads/master@{#37474}

src/ast/ast-value-factory.h

@@ -267,6 +267,7 @@ class AstValue : public ZoneObject {
   F(prototype, "prototype")                     \
   F(return, "return")                           \
   F(set_space, "set ")                          \
+  F(star_default_star, "*default*")             \
   F(this, "this")                               \
   F(this_function, ".this_function")            \
   F(throw, "throw")                             \

src/parsing/parser.h

@@ -782,18 +782,15 @@ class Parser : public ParserBase<ParserTraits> {
                                    bool* ok);
   Statement* ParseFunctionDeclaration(bool* ok);
   Statement* ParseHoistableDeclaration(ZoneList<const AstRawString*>* names,
-                                      bool* ok);
+                                       bool default_export, bool* ok);
   Statement* ParseHoistableDeclaration(int pos, ParseFunctionFlags flags,
                                        ZoneList<const AstRawString*>* names,
-                                       bool* ok);
+                                       bool default_export, bool* ok);
   Statement* ParseAsyncFunctionDeclaration(ZoneList<const AstRawString*>* names,
-                                           bool* ok);
+                                           bool default_export, bool* ok);
   Expression* ParseAsyncFunctionExpression(bool* ok);
-  Statement* ParseFunctionDeclaration(int pos, bool is_generator,
-                                      ZoneList<const AstRawString*>* names,
-                                      bool* ok);
   Statement* ParseClassDeclaration(ZoneList<const AstRawString*>* names,
-                                   bool* ok);
+                                   bool default_export, bool* ok);
   Statement* ParseNativeDeclaration(bool* ok);
   Block* ParseBlock(ZoneList<const AstRawString*>* labels, bool* ok);
   Block* ParseBlock(ZoneList<const AstRawString*>* labels,

test/cctest/test-parsing.cc

@@ -5510,8 +5510,8 @@ TEST(BasicImportExportParsing) {
       "export default function() {}",
       "export default function*() {}",
       "export default class C {}",
-      "export default class {}"
-      "export default class extends C {}"
+      "export default class {}",
+      "export default class extends C {}",
       "export default 42",
       "var x; export default x = 7",
       "export { Q } from 'somemodule.js';",