Improve error messages and reporting in GN

tools/gn/setup.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/setup.h"
 
 #include <stdlib.h>
 
 #include <algorithm>
 #include <sstream>
@@ skipping 145 matching lines @@
       check_for_unused_overrides_(other.check_for_unused_overrides_),
       check_public_headers_(other.check_public_headers_) {
   loader_->set_complete_callback(base::Bind(&DecrementWorkCount));
 }
 
 CommonSetup::~CommonSetup() {
 }
 
 void CommonSetup::RunPreMessageLoop() {
   // Load the root build file.
-  loader_->Load(root_build_file_, Label());
+  loader_->Load(root_build_file_, LocationRange(), Label());
 
   // Will be decremented with the loader is drained.
   g_scheduler->IncrementWorkCount();
 }
 
 bool CommonSetup::RunPostMessageLoop() {
   Err err;
   if (check_for_bad_items_) {
     if (!builder_->CheckForBadItems(&err)) {
       err.PrintToStdout();
@@ skipping 419 matching lines @@
 }
 
 void DependentSetup::RunPreMessageLoop() {
   CommonSetup::RunPreMessageLoop();
 }
 
 bool DependentSetup::RunPostMessageLoop() {
   return CommonSetup::RunPostMessageLoop();
 }