Fix a test failure as GetFileSize() will not set the size if it fails

base/file_util_unittest.cc

 // Copyright (c) 2012 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 "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <shellapi.h>
 #include <shlobj.h>
@@ skipping 2342 matching lines @@
   EXPECT_TRUE(file_util::ReadFromFD(fd, buffer, image_size));
   delete[] buffer;
 }
 
 TEST_F(FileUtilTest, NonExistentContentUriTest) {
   base::FilePath path("content://foo.bar");
   EXPECT_TRUE(path.IsContentUri());
   EXPECT_FALSE(base::PathExists(path));
   // Size should be smaller than 0.
   int64 size;
-  file_util::GetFileSize(path, &size);
-  EXPECT_GT(0, size);
+  EXPECT_FALSE(file_util::GetFileSize(path, &size));
 
   // We should not be able to read the file.
   int fd = base::OpenContentUriForRead(path);
   EXPECT_EQ(-1, fd);
 }
 #endif
 
 #endif  // defined(OS_POSIX)
 
 }  // namespace