GN: Add the ability to trim whitespace from script results.

tools/gn/function_read_file.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 "base/file_util.h"
 #include "tools/gn/err.h"
 #include "tools/gn/filesystem_utils.h"
 #include "tools/gn/functions.h"
 #include "tools/gn/input_conversion.h"
 #include "tools/gn/input_file.h"
 #include "tools/gn/scheduler.h"
 
 // TODO(brettw) consider removing this. I originally wrote it for making the
 // WebKit bindings but misundersood what was required, and didn't need to
 // use this. This seems to have a high potential for misuse.
 
 namespace functions {
 
 const char kReadFile[] = "read_file";
 const char kReadFile_Help[] =
     "read_file: Read a file into a variable.\n"
     "\n"
-    "  read_file(filename, how_to_read)\n"
+    "  read_file(filename, input_conversion)\n"
     "\n"
     "  Whitespace will be trimmed from the end of the file. Throws an error\n"
     "  if the file can not be opened.\n"
     "\n"
     "Arguments\n"
     "\n"
     "  filename\n"
     "      Filename to read, relative to the build file.\n"
     "\n"
     "  input_conversion\n"
@@ skipping 29 matching lines @@
   if (!base::ReadFileToString(file_path, &file_contents)) {
     *err = Err(args[0], "Could not read file.",
                "I resolved this to \"" + FilePathToUTF8(file_path) + "\".");
     return Value();
   }
 
   return ConvertInputToValue(file_contents, function, args[1], err);
 }
 
 }  // namespace functions