Get rid of the unused native code StringAddStub.

src/ia32/code-stubs-ia32.h

Index: src/ia32/code-stubs-ia32.h
diff --git a/src/ia32/code-stubs-ia32.h b/src/ia32/code-stubs-ia32.h
index 0982fe1fdce3c0bca90e951f3891895d7f06055a..e383a9d7e9e476b3fe92536bf91a4d0d33074bc2 100644
--- a/src/ia32/code-stubs-ia32.h
+++ b/src/ia32/code-stubs-ia32.h
@@ -63,17 +63,6 @@ class StoreBufferOverflowStub: public PlatformCodeStub {
 
 class StringHelper : public AllStatic {
  public:
-  // Generate code for copying characters using a simple loop. This should only
-  // be used in places where the number of characters is small and the
-  // additional setup and checking in GenerateCopyCharactersREP adds too much
-  // overhead. Copying of overlapping regions is not supported.
-  static void GenerateCopyCharacters(MacroAssembler* masm,
-                                     Register dest,
-                                     Register src,
-                                     Register count,
-                                     Register scratch,
-                                     bool ascii);
-
   // Generate code for copying characters using the rep movs instruction.
   // Copies ecx characters from esi to edi. Copying of overlapping regions is
   // not supported.
@@ -84,23 +73,6 @@ class StringHelper : public AllStatic {
                                         Register scratch,  // Neither of above.
                                         bool ascii);
 
-  // Probe the string table for a two character string. If the string
-  // requires non-standard hashing a jump to the label not_probed is
-  // performed and registers c1 and c2 are preserved. In all other
-  // cases they are clobbered. If the string is not found by probing a
-  // jump to the label not_found is performed. This jump does not
-  // guarantee that the string is not in the string table. If the
-  // string is found the code falls through with the string in
-  // register eax.
-  static void GenerateTwoCharacterStringTableProbe(MacroAssembler* masm,
-                                                   Register c1,
-                                                   Register c2,
-                                                   Register scratch1,
-                                                   Register scratch2,
-                                                   Register scratch3,
-                                                   Label* not_probed,
-                                                   Label* not_found);
-
   // Generate string hash.
   static void GenerateHashInit(MacroAssembler* masm,
                                Register hash,
@@ -119,31 +91,6 @@ class StringHelper : public AllStatic {
 };
 
 
-class StringAddStub: public PlatformCodeStub {
- public:
-  explicit StringAddStub(StringAddFlags flags) : flags_(flags) {}
-
- private:
-  Major MajorKey() { return StringAdd; }
-  int MinorKey() { return flags_; }
-
-  void Generate(MacroAssembler* masm);
-
-  void GenerateConvertArgument(MacroAssembler* masm,
-                               int stack_offset,
-                               Register arg,
-                               Register scratch1,
-                               Register scratch2,
-                               Register scratch3,
-                               Label* slow);
-
-  void GenerateRegisterArgsPush(MacroAssembler* masm);
-  void GenerateRegisterArgsPop(MacroAssembler* masm, Register temp);
-
-  const StringAddFlags flags_;
-};
-
-
 class SubStringStub: public PlatformCodeStub {
  public:
   SubStringStub() {}