[turbofan] refactor pipeline to use hydrogen like Run calls

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 40 matching lines @@
 
   void set_ast_context(AstContext* ctx) { ast_context_ = ctx; }
   void set_breakable(BreakableScope* brk) { breakable_ = brk; }
   void set_execution_context(ContextScope* ctx) { execution_context_ = ctx; }
 
   // Support for control flow builders. The concrete type of the environment
   // depends on the graph builder, but environments themselves are not virtual.
   typedef StructuredGraphBuilder::Environment BaseEnvironment;
   virtual BaseEnvironment* CopyEnvironment(BaseEnvironment* env) OVERRIDE;
 
-  // TODO(mstarzinger): The pipeline only needs to be a friend to access the
-  // function context. Remove as soon as the context is a parameter.
-  friend class Pipeline;
-
   // Getters for values in the activation record.
   Node* GetFunctionClosure();
   Node* GetFunctionContext();
 
   //
   // The following build methods all generate graph fragments and return one
   // resulting node. The operand stack height remains the same, variables and
   // other dependencies tracked by the environment might be mutated though.
   //
 
@@ skipping 369 matching lines @@
 
 Scope* AstGraphBuilder::current_scope() const {
   return execution_context_->scope();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_AST_GRAPH_BUILDER_H_