Hook up symbol files to the Windows GN build.

tools/gn/variables.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/variables.h"
 
 namespace variables {
 
 // Built-in variables ----------------------------------------------------------
 
@@ skipping 198 matching lines @@
     "  action(\"myscript\") {\n"
     "    # Pass the generated output dir to the script.\n"
     "    args = [ \"-o\", rebase_path(target_gen_dir, root_build_dir) ]"
     "\n"
     "  }\n";
 
 const char kTargetOutDir[] = "target_out_dir";
 const char kTargetOutDir_HelpShort[] =
     "target_out_dir: [string] Directory for target output files.";
 const char kTargetOutDir_Help[] =
-    "target_out_dir: [string] Directory for target output files."
+    "target_out_dir: [string] Directory for target output files.\n"
     "\n"
     "  Absolute path to the target's generated file directory. If your\n"
     "  current target is in \"//tools/doom_melon\" then this value might be\n"
     "  \"//out/Debug/obj/tools/doom_melon\". It will not have a trailing\n"
     "  slash.\n"
     "\n"
     "  This is primarily useful for setting up arguments for calling\n"
     "  scripts. If you are passing this to a script, you will want to pass it\n"
     "  through rebase_path() (see \"gn help rebase_path\") to convert it\n"
     "  to be relative to the build directory.\n"
@@ skipping 658 matching lines @@
     INSERT_VARIABLE(Script)
     INSERT_VARIABLE(Sources)
     INSERT_VARIABLE(Visibility)
   }
   return info_map;
 }
 
 #undef INSERT_VARIABLE
 
 }  // namespace variables