Add installer_util_unittests to the GN windows build

chrome/installer/util/delete_after_reboot_helper_unittest.cc

 // Copyright (c) 2011 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 <windows.h>
 #include <shlobj.h>
 
 #include "base/files/file_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string_util.h"
@@ skipping 35 matching lines @@
           HKEY_LOCAL_MACHINE, kSessionManagerKey,
           KEY_CREATE_SUB_KEY | KEY_SET_VALUE);
       if (!session_manager_key.Handle()) {
         // Couldn't open / create the key.
         DLOG(ERROR) << "Failed to open session manager key for writing.";
       }
 
       std::vector<char> buffer;
       StringArrayToMultiSZBytes(original_pending_moves_, &buffer);
       session_manager_key.WriteValue(kPendingFileRenameOps, &buffer[0],
-                                     buffer.size(), REG_MULTI_SZ);
+                                     static_cast<int>(buffer.size()),
+                                     REG_MULTI_SZ);
     }
   }
 
   // Compares two buffers of size len. Returns true if they are equal,
   // false otherwise. Standard warnings about making sure the buffers
   // are at least len chars long apply.
   template<class Type>
   bool CompareBuffers(Type* buf1, Type* buf2, int len) {
     Type* comp1 = buf1;
     Type* comp2 = buf2;
@@ skipping 176 matching lines @@
 
   EXPECT_EQ(initial_pending_moves_size, pending_moves.size());
 
   std::vector<PendingMove>::const_iterator check_iter(pending_moves.begin());
   for (; check_iter != pending_moves.end(); ++check_iter) {
     base::FilePath move_path(check_iter->first);
     EXPECT_FALSE(MatchPendingDeletePath(short_temp_file, move_path));
   }
 }