[stubs] Introduce ToIntegerStub and unify the handling of %_ToInteger.

src/full-codegen/x87/full-codegen-x87.cc

Index: src/full-codegen/x87/full-codegen-x87.cc
diff --git a/src/full-codegen/x87/full-codegen-x87.cc b/src/full-codegen/x87/full-codegen-x87.cc
index 1d0a4052e4a182bf25a735116a0ef3494bc40356..4452fa1af65dfb510f02ac4c3a1d613ef7c63949 100644
--- a/src/full-codegen/x87/full-codegen-x87.cc
+++ b/src/full-codegen/x87/full-codegen-x87.cc
@@ -2995,23 +2995,6 @@ void FullCodeGenerator::EmitTwoByteSeqStringSetChar(CallRuntime* expr) {
 }
 
 
-void FullCodeGenerator::EmitToInteger(CallRuntime* expr) {
-  ZoneList<Expression*>* args = expr->arguments();
-  DCHECK_EQ(1, args->length());
-
-  // Load the argument into eax and convert it.
-  VisitForAccumulatorValue(args->at(0));
-
-  // Convert the object to an integer.
-  Label done_convert;
-  __ JumpIfSmi(eax, &done_convert, Label::kNear);
-  __ Push(eax);
-  __ CallRuntime(Runtime::kToInteger);
-  __ bind(&done_convert);
-  context()->Plug(eax);
-}
-
-
 void FullCodeGenerator::EmitStringCharFromCode(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 1);