Remove unused StringCharCodeAt stub.

src/code-stubs.h

Index: src/code-stubs.h
diff --git a/src/code-stubs.h b/src/code-stubs.h
index f9f7b82382ad60457deb315c47b13f5c97e563e9..6af45d54faf08f83ad9295f9f35c5ee2816054dc 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -40,7 +40,6 @@ namespace internal {
   V(GenericBinaryOp)                     \
   V(TypeRecordingBinaryOp)               \
   V(StringAdd)                           \
-  V(StringCharAt)                        \
   V(SubString)                           \
   V(StringCompare)                       \
   V(SmiOp)                               \
@@ -438,18 +437,6 @@ class MathPowStub: public CodeStub {
 };
 
 
-class StringCharAtStub: public CodeStub {
- public:
-  StringCharAtStub() {}
-
- private:
-  Major MajorKey() { return StringCharAt; }
-  int MinorKey() { return 0; }
-
-  void Generate(MacroAssembler* masm);
-};
-
-
 class ICCompareStub: public CodeStub {
  public:
   ICCompareStub(Token::Value op, CompareIC::State state)