[parser] improve inferred function names for async arrow functions

test/cctest/test-parsing.cc

Index: test/cctest/test-parsing.cc
diff --git a/test/cctest/test-parsing.cc b/test/cctest/test-parsing.cc
index b5e544fb3b3fe5a4b9814aa21cd47167d44ec9b3..9faa0a40ea70d40ea96a7d216795a46bcf699e9d 100644
--- a/test/cctest/test-parsing.cc
+++ b/test/cctest/test-parsing.cc
@@ -7840,34 +7840,34 @@ TEST(AsyncAwaitErrors) {
     "async function foo() { function await() {} }",
 
     // Henrique Ferreiro's bug (tm)
-    "(async function foo() { } foo => 1)",
-    "(async function foo() { } () => 1)",
-    "(async function foo() { } => 1)",
-    "(async function() { } foo => 1)",
+    "(async function foo1() { } foo2 => 1)",
+    "(async function foo3() { } () => 1)",
+    "(async function foo4() { } => 1)",
+    "(async function() { } foo5 => 1)",
     "(async function() { } () => 1)",
     "(async function() { } => 1)",
-    "(async.foo => 1)",
-    "(async.foo foo => 1)",
-    "(async.foo () => 1)",
-    "(async().foo => 1)",
-    "(async().foo foo => 1)",
-    "(async().foo () => 1)",
-    "(async['foo'] => 1)",
-    "(async['foo'] foo => 1)",
-    "(async['foo'] () => 1)",
-    "(async()['foo'] => 1)",
-    "(async()['foo'] foo => 1)",
-    "(async()['foo'] () => 1)",
-    "(async`foo` => 1)",
-    "(async`foo` foo => 1)",
-    "(async`foo` () => 1)",
-    "(async`foo`.bar => 1)",
-    "(async`foo`.bar foo => 1)",
-    "(async`foo`.bar () => 1)",
+    "(async.foo6 => 1)",
+    "(async.foo7 foo8 => 1)",
+    "(async.foo9 () => 1)",
+    "(async().foo10 => 1)",
+    "(async().foo11 foo12 => 1)",
+    "(async().foo13 () => 1)",
+    "(async['foo14'] => 1)",
+    "(async['foo15'] foo16 => 1)",
+    "(async['foo17'] () => 1)",
+    "(async()['foo18'] => 1)",
+    "(async()['foo19'] foo20 => 1)",
+    "(async()['foo21'] () => 1)",
+    "(async`foo22` => 1)",
+    "(async`foo23` foo24 => 1)",
+    "(async`foo25` () => 1)",
+    "(async`foo26`.bar27 => 1)",
+    "(async`foo28`.bar29 foo30 => 1)",
+    "(async`foo31`.bar32 () => 1)",
 
     // v8:5148 assert that errors are still thrown for calls that may have been
     // async functions
-    "async({ foo = 1 })",
+    "async({ foo33 = 1 })",
     NULL
   };