[turbofan] Remove the JSGraph dependency from the ControlFlowOptimizer.

test/unittests/compiler/graph-unittest.cc

 // Copyright 2014 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 "test/unittests/compiler/graph-unittest.h"
 
 #include "src/compiler/node-properties.h"
 #include "test/unittests/compiler/node-test-utils.h"
 
 namespace v8 {
@@ skipping 63 matching lines @@
       Unique<HeapObject>::CreateImmovable(factory()->true_value()));
 }
 
 
 Node* GraphTest::UndefinedConstant() {
   return HeapConstant(
       Unique<HeapObject>::CreateImmovable(factory()->undefined_value()));
 }
 
 
+Node* GraphTest::EmptyFrameState() {
+  Node* state_values = graph()->NewNode(common()->StateValues(0));
+  return graph()->NewNode(
+      common()->FrameState(JS_FRAME, BailoutId::None(),
+                           OutputFrameStateCombine::Ignore()),
+      state_values, state_values, state_values, NumberConstant(0),
+      UndefinedConstant(), graph()->start());
+}
+
+
 Matcher<Node*> GraphTest::IsFalseConstant() {
   return IsHeapConstant(
       Unique<HeapObject>::CreateImmovable(factory()->false_value()));
 }
 
 
 Matcher<Node*> GraphTest::IsTrueConstant() {
   return IsHeapConstant(
       Unique<HeapObject>::CreateImmovable(factory()->true_value()));
 }
@@ skipping 35 matching lines @@
   EXPECT_LT(0, n0->id());
   EXPECT_LT(0, n1->id());
   EXPECT_NE(n0->id(), n1->id());
   EXPECT_EQ(&kDummyOperator, n0->op());
   EXPECT_EQ(&kDummyOperator, n1->op());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8