Fix help and error messages.

tools/gn/function_write_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 <iostream>
 #include <sstream>
 
 #include "base/file_util.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
@@ skipping 24 matching lines @@
     "      Filename to write. This must be within the output directory.\n"
     "\n"
     "  data:\n"
     "      The list or string to write.\n";
 
 Value RunWriteFile(Scope* scope,
                    const FunctionCallNode* function,
                    const std::vector<Value>& args,
                    Err* err) {
   if (args.size() != 2) {
-    *err = Err(function->function(), "Wrong number of args to write_file",
+    *err = Err(function->function(), "Wrong number of arguments to write_file",
                "I expected two arguments.");
     return Value();
   }
 
   // Compute the file name and make sure it's in the output dir.
   if (!args[0].VerifyTypeIs(Value::STRING, err))
     return Value();
   const SourceDir& cur_dir = scope->GetSourceDir();
   SourceFile source_file = cur_dir.ResolveRelativeFile(args[0].string_value());
   if (!EnsureStringIsInOutputDir(
@@ skipping 24 matching lines @@
   if (file_util::WriteFile(file_path, contents_string.c_str(), int_size)
       != int_size) {
     *err = Err(function->function(), "Unable to write file.",
                "I was writing \"" + FilePathToUTF8(file_path) + "\".");
     return Value();
   }
   return Value();
 }
 
 }  // namespace functions