Port flush_cache tool.

chrome/tools/perf/flush_cache/flush_cache.cc

Index: chrome/tools/perf/flush_cache/flush_cache.cc
===================================================================
--- chrome/tools/perf/flush_cache/flush_cache.cc	(revision 6884)
+++ chrome/tools/perf/flush_cache/flush_cache.cc	(working copy)
@@ -2,9 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// This little program attempts to flush the disk cache for some files.
+// This little program attempts to flush the system cache for some files.
 // It's useful for testing Chrome with a cold database.
 
+#include "base/file_path.h"
 #include "base/string_piece.h"
 #include "base/process_util.h"
 #include "base/sys_string_conversions.h"
@@ -20,7 +21,8 @@
 
   for (int i = 1; i < argc; ++i) {
     std::wstring filename = base::SysNativeMBToWide(argv[i]);
-    if (!file_util::EvictFileFromSystemCache(filename.c_str())) {
+    FilePath path = FilePath::FromWStringHack(filename);
+    if (!file_util::EvictFileFromSystemCache(path)) {
       fprintf(stderr, "Failed to evict %s from cache -- is it a directory?\n",
               argv[i]);
     }