[builtins] Turn LoadIC_Miss and LoadIC_Slow builtins to TurboFan code stubs.

src/ic/ic.h

Index: src/ic/ic.h
diff --git a/src/ic/ic.h b/src/ic/ic.h
index 85c84746ab6b290edc9e6eca4000f753e234337b..f0dd478ff08c57b4bcd4be293ccd9cf558c47035 100644
--- a/src/ic/ic.h
+++ b/src/ic/ic.h
@@ -300,9 +300,7 @@ class LoadIC : public IC {
   static void Clear(Isolate* isolate, Code* host, LoadICNexus* nexus);
 
  protected:
-  Handle<Code> slow_stub() const {
-    return isolate()->builtins()->LoadIC_Slow();
-  }
+  Handle<Code> slow_stub() const;
 
   // Update the inline cache and the global stub cache based on the
   // lookup result.