Eliminate special keyed load string stub in favor of uniform handlers.

src/ic/x64/ic-x64.cc

Index: src/ic/x64/ic-x64.cc
diff --git a/src/ic/x64/ic-x64.cc b/src/ic/x64/ic-x64.cc
index ad79f3042dbdb7c3b009eb21e0e3c894399451a6..4c512f170107d4425b235078671b2deeb5d32007 100644
--- a/src/ic/x64/ic-x64.cc
+++ b/src/ic/x64/ic-x64.cc
@@ -403,32 +403,6 @@ void KeyedLoadIC::GenerateGeneric(MacroAssembler* masm) {
 }
 
 
-void KeyedLoadIC::GenerateString(MacroAssembler* masm) {
-  // Return address is on the stack.
-  Label miss;
-
-  Register receiver = LoadDescriptor::ReceiverRegister();
-  Register index = LoadDescriptor::NameRegister();
-  Register scratch = rbx;
-  Register result = rax;
-  DCHECK(!scratch.is(receiver) && !scratch.is(index));
-
-  StringCharAtGenerator char_at_generator(receiver, index, scratch, result,
-                                          &miss,  // When not a string.
-                                          &miss,  // When not a number.
-                                          &miss,  // When index out of range.
-                                          STRING_INDEX_IS_ARRAY_INDEX);
-  char_at_generator.GenerateFast(masm);
-  __ ret(0);
-
-  StubRuntimeCallHelper call_helper;
-  char_at_generator.GenerateSlow(masm, call_helper);
-
-  __ bind(&miss);
-  GenerateMiss(masm);
-}
-
-
 static void KeyedStoreGenerateGenericHelper(
     MacroAssembler* masm, Label* fast_object, Label* fast_double, Label* slow,
     KeyedStoreCheckMap check_map, KeyedStoreIncrementLength increment_length) {