Introduce a BuiltinsConstructStub that sets up new.target and does a [[call]] per ES6 9.3.2

src/crankshaft/hydrogen.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/crankshaft/hydrogen.h"
 
 #include <sstream>
 
 #include "src/allocation-site-scopes.h"
 #include "src/ast-numbering.h"
@@ skipping 9908 matching lines @@
   if (function->IsConstant() &&
       HConstant::cast(function)->handle(isolate())->IsJSFunction()) {
     Handle<Object> constant = HConstant::cast(function)->handle(isolate());
     expr->SetKnownGlobalTarget(Handle<JSFunction>::cast(constant));
   }
 
   if (FLAG_inline_construct &&
       expr->IsMonomorphic() &&
       IsAllocationInlineable(expr->target())) {
     Handle<JSFunction> constructor = expr->target();
+    DCHECK(
+        constructor->shared()->construct_stub() ==
+            isolate()->builtins()->builtin(Builtins::kJSConstructStubGeneric) ||
+        constructor->shared()->construct_stub() ==
+            isolate()->builtins()->builtin(Builtins::kJSConstructStubApi));
     HValue* check = Add<HCheckValue>(function, constructor);
 
     // Force completion of inobject slack tracking before generating
     // allocation code to finalize instance size.
     if (constructor->IsInobjectSlackTrackingInProgress()) {
       constructor->CompleteInobjectSlackTracking();
     }
 
     // Calculate instance size from initial map of constructor.
     DCHECK(constructor->has_initial_map());
@@ skipping 3691 matching lines @@
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8