Remove dead code for inline string hashing.

src/arm64/code-stubs-arm64.h

Index: src/arm64/code-stubs-arm64.h
diff --git a/src/arm64/code-stubs-arm64.h b/src/arm64/code-stubs-arm64.h
index d55c8cbb5882fcb299add702dc89f824a3afc1c1..f42f8b5de40eaee1cef168ffb83cb0a4fe9997ca 100644
--- a/src/arm64/code-stubs-arm64.h
+++ b/src/arm64/code-stubs-arm64.h
@@ -16,21 +16,6 @@ void ArrayNativeCode(MacroAssembler* masm, Label* call_generic_code);
 
 class StringHelper : public AllStatic {
  public:
-  // TODO(all): These don't seem to be used any more. Delete them.
-
-  // Generate string hash.
-  static void GenerateHashInit(MacroAssembler* masm,
-                               Register hash,
-                               Register character);
-
-  static void GenerateHashAddCharacter(MacroAssembler* masm,
-                                       Register hash,
-                                       Register character);
-
-  static void GenerateHashGetHash(MacroAssembler* masm,
-                                  Register hash,
-                                  Register scratch);
-
   // Compares two flat ASCII strings and returns result in x0.
   static void GenerateCompareFlatAsciiStrings(
       MacroAssembler* masm, Register left, Register right, Register scratch1,