Revert "Make FrameStates recursive (to be used for inlining)."

src/compiler/ast-graph-builder.h

 // 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.
 
 #ifndef V8_COMPILER_AST_GRAPH_BUILDER_H_
 #define V8_COMPILER_AST_GRAPH_BUILDER_H_
 
 #include "src/v8.h"
 
 #include "src/ast.h"
@@ skipping 242 matching lines @@
   }
   void Drop(int depth) {
     DCHECK(depth >= 0 && depth <= stack_height());
     values()->erase(values()->end() - depth, values()->end());
   }
 
   // Preserve a checkpoint of the environment for the IR graph. Any
   // further mutation of the environment will not affect checkpoints.
   Node* Checkpoint(BailoutId ast_id, OutputFrameStateCombine combine);
 
- protected:
-  AstGraphBuilder* builder() const {
-    return reinterpret_cast<AstGraphBuilder*>(
-        StructuredGraphBuilder::Environment::builder());
-  }
-
  private:
   void UpdateStateValues(Node** state_values, int offset, int count);
 
   int parameters_count_;
   int locals_count_;
   Node* parameters_node_;
   Node* locals_node_;
   Node* stack_node_;
 };
 
@@ skipping 142 matching lines @@
 };
 
 Scope* AstGraphBuilder::current_scope() const {
   return execution_context_->scope();
 }
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_AST_GRAPH_BUILDER_H_