Remove dead code for inline string hashing.

src/x64/code-stubs-x64.h

Index: src/x64/code-stubs-x64.h
diff --git a/src/x64/code-stubs-x64.h b/src/x64/code-stubs-x64.h
index c8e3835dc46348349ce56b03d37dc87e9b91b6a4..4d55dac7fbb87a169fb45ab43f1b8d11983d82f6 100644
--- a/src/x64/code-stubs-x64.h
+++ b/src/x64/code-stubs-x64.h
@@ -25,22 +25,6 @@ class StringHelper : public AllStatic {
                                      Register count,
                                      String::Encoding encoding);
 
-
-  // Generate string hash.
-  static void GenerateHashInit(MacroAssembler* masm,
-                               Register hash,
-                               Register character,
-                               Register scratch);
-
-  static void GenerateHashAddCharacter(MacroAssembler* masm,
-                                       Register hash,
-                                       Register character,
-                                       Register scratch);
-
-  static void GenerateHashGetHash(MacroAssembler* masm,
-                                  Register hash,
-                                  Register scratch);
-
   // Compares two flat ASCII strings and returns result in rax.
   static void GenerateCompareFlatAsciiStrings(
       MacroAssembler* masm, Register left, Register right, Register scratch1,