Remove GN GYP generator.

tools/gn/function_toolchain.cc

 // Copyright (c) 2013 The Chromium 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 "tools/gn/err.h"
 #include "tools/gn/functions.h"
 #include "tools/gn/parse_tree.h"
 #include "tools/gn/scheduler.h"
 #include "tools/gn/scope.h"
 #include "tools/gn/settings.h"
@@ skipping 95 matching lines @@
   scoped_ptr<Toolchain> toolchain(new Toolchain(scope->settings(), label));
   toolchain->set_defined_from(function);
 
   Scope block_scope(scope);
   block_scope.SetProperty(&kToolchainPropertyKey, toolchain.get());
   block->ExecuteBlockInScope(&block_scope, err);
   block_scope.SetProperty(&kToolchainPropertyKey, NULL);
   if (err->has_error())
     return Value();
 
-  // Extract the gyp_header contents, if any.
-  const Value* gyp_header_value =
-      block_scope.GetValue(variables::kGypHeader, true);
-  if (gyp_header_value) {
-    if (!gyp_header_value->VerifyTypeIs(Value::STRING, err))
-      return Value();
-    toolchain->set_gyp_header(gyp_header_value->string_value());
-  }
-
   if (!block_scope.CheckForUnusedVars(err))
     return Value();
 
   scope->settings()->build_settings()->ItemDefined(toolchain.PassAs<Item>());
   return Value();
 }
 
 // tool ------------------------------------------------------------------------
 
 const char kTool[] = "tool";
@@ skipping 168 matching lines @@
     return Value();
 
   Scope::KeyValueMap values;
   block_scope.GetCurrentScopeValues(&values);
   toolchain->args() = values;
 
   return Value();
 }
 
 }  // namespace functions