Expose a function to get the path to a DLL.

chrome/installer/util/module_util_win.h

Index: chrome/installer/util/module_util_win.h
diff --git a/chrome/installer/util/module_util_win.h b/chrome/installer/util/module_util_win.h
new file mode 100644
index 0000000000000000000000000000000000000000..da5733e4cce95f1cf40839cb5967b553708183b0
--- /dev/null
+++ b/chrome/installer/util/module_util_win.h
@@ -0,0 +1,25 @@
+// Copyright (c) 2015 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.
+
+// This file defines a utility function to get the full path of a module.
+
+#ifndef CHROME_INSTALLER_UTIL_MODULE_UTIL_WIN_H_
+#define CHROME_INSTALLER_UTIL_MODULE_UTIL_WIN_H_
+
+#include "base/files/file_path.h"
+#include "base/strings/string16.h"
+
+namespace installer {
+
+// Returns the full path to a module named |module_name|, or an empty path if

[grt (UTC plus 2), 2015/10/30 15:45:59]

this comment isn't quite right. an empty path is returned if the current module
doesn't have a version resource. the function does not validate that the file
exists if it peeks into a version directory. i think it's fine to change the
comment to match the impl rather than the other way around.

[fdoray, 2015/10/30 17:22:15]

Done.

+// the module is not found. The searched module must be in the same directory as
+// the current executable, or in a version subdirectory. On output, if the
+// module is in a version subdirectory, |version| is populated with the version
+// of the module.
+base::FilePath GetModulePath(const base::char16* module_name,

[grt (UTC plus 2), 2015/10/30 15:45:59]

nit: pass module_name by const-ref

[grt (UTC plus 2), 2015/10/30 15:57:58]

oops, that doesn't make sense (i read it as string16 rather than char16). how
about using StringPiece16 here? this will allow callers to pass either a char16*
or a string16.

[fdoray, 2015/10/30 17:22:15]

Done.

+                             base::string16* version);
+
+}  // namespace installer
+
+#endif  // CHROME_INSTALLER_UTIL_MODULE_UTIL_WIN_H_