Make one-character strings into symbols more agressively.

Review URL: http://codereview.chromium.org/7840029

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9175 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap.cc

@@ -3623,6 +3623,9 @@ MaybeObject* Heap::ReinitializeJSGlobalProxy(JSFunction* constructor,
 
 MaybeObject* Heap::AllocateStringFromAscii(Vector<const char> string,
                                            PretenureFlag pretenure) {
+  if (string.length() == 1) {
+    return Heap::LookupSingleCharacterStringFromCode(string[0]);
+  }
   Object* result;
   { MaybeObject* maybe_result =
         AllocateRawAsciiString(string.length(), pretenure);

test/cctest/test-profile-generator.cc

@@ -37,16 +37,16 @@ TEST(TokenEnumerator) {
   TokenEnumerator te;
   CHECK_EQ(TokenEnumerator::kNoSecurityToken, te.GetTokenId(NULL));
   v8::HandleScope hs;
-  v8::Local<v8::String> token1(v8::String::New("1"));
+  v8::Local<v8::String> token1(v8::String::New("1x"));
   CHECK_EQ(0, te.GetTokenId(*v8::Utils::OpenHandle(*token1)));
   CHECK_EQ(0, te.GetTokenId(*v8::Utils::OpenHandle(*token1)));
-  v8::Local<v8::String> token2(v8::String::New("2"));
+  v8::Local<v8::String> token2(v8::String::New("2x"));
   CHECK_EQ(1, te.GetTokenId(*v8::Utils::OpenHandle(*token2)));
   CHECK_EQ(1, te.GetTokenId(*v8::Utils::OpenHandle(*token2)));
   CHECK_EQ(0, te.GetTokenId(*v8::Utils::OpenHandle(*token1)));
   {
     v8::HandleScope hs;
-    v8::Local<v8::String> token3(v8::String::New("3"));
+    v8::Local<v8::String> token3(v8::String::New("3x"));
     CHECK_EQ(2, te.GetTokenId(*v8::Utils::OpenHandle(*token3)));
     CHECK_EQ(1, te.GetTokenId(*v8::Utils::OpenHandle(*token2)));
     CHECK_EQ(0, te.GetTokenId(*v8::Utils::OpenHandle(*token1)));