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

src/full-codegen/full-codegen.cc

Index: src/full-codegen/full-codegen.cc
diff --git a/src/full-codegen/full-codegen.cc b/src/full-codegen/full-codegen.cc
index d29d6123da8ea6767a0b7a89f2c2a34876dba8c3..a2cf07bd3ae05d2170221b6857e64bef47c3fa05 100644
--- a/src/full-codegen/full-codegen.cc
+++ b/src/full-codegen/full-codegen.cc
@@ -588,6 +588,9 @@ void FullCodeGenerator::EmitToLength(CallRuntime* expr) {
   EmitIntrinsicAsStubCall(expr, CodeFactory::ToLength(isolate()));
 }
 
+void FullCodeGenerator::EmitToInteger(CallRuntime* expr) {
+  EmitIntrinsicAsStubCall(expr, CodeFactory::ToInteger(isolate()));
+}
 
 void FullCodeGenerator::EmitToNumber(CallRuntime* expr) {
   EmitIntrinsicAsStubCall(expr, CodeFactory::ToNumber(isolate()));