[turbofan]: Add a context relaxer reducer

test/unittests/compiler/liveness-analyzer-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 "src/compiler/js-graph.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/liveness-analyzer.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/state-values-utils.h"
 #include "test/unittests/compiler/graph-unittest.h"
@@ skipping 42 matching lines @@
     ZoneVector<Node*> local_inputs(locals_count_, nullptr, zone());
     for (int i = 0; i < locals_count_; i++) {
       local_inputs[i] = jsgraph()->Int32Constant(i + first_const);
     }
     Node* locals =
         graph()->NewNode(locals_op, locals_count_, &local_inputs.front());
 
     const FrameStateFunctionInfo* state_info =
         common()->CreateFrameStateFunctionInfo(
             FrameStateType::kJavaScriptFunction, 0, locals_count_,
-            Handle<SharedFunctionInfo>());
+            Handle<SharedFunctionInfo>(), CALL_MAINTAINS_NATIVE_CONTEXT);
 
     const Operator* op = common()->FrameState(
         BailoutId(ast_num), OutputFrameStateCombine::Ignore(), state_info);
     Node* result = graph()->NewNode(op, empty_values_, locals, empty_values_,
                                     jsgraph()->UndefinedConstant(),
                                     jsgraph()->UndefinedConstant());
 
     current_block_->Checkpoint(result);
     return result;
   }
@@ skipping 294 matching lines @@
   EXPECT_THAT(c1_in_loop, IsCheckpointModuloLiveness(".L.L"));
   EXPECT_THAT(c2_in_loop, IsCheckpointModuloLiveness("LL.L"));
 
   EXPECT_THAT(c1_end, IsCheckpointModuloLiveness(".LL."));
   EXPECT_THAT(c2_end, IsCheckpointModuloLiveness("...."));
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8