FilePath: Remove most of ToWStringHack, adding a LossyDisplayName()

base/file_util_unittest.cc

Index: base/file_util_unittest.cc
diff --git a/base/file_util_unittest.cc b/base/file_util_unittest.cc
index 6ea94e4d98518c96dfd4a9fd8acde8175fda99b9..ea29df521720c8de2c4801c10f7c8e2a96cadd83 100644
--- a/base/file_util_unittest.cc
+++ b/base/file_util_unittest.cc
@@ -163,7 +163,7 @@ class FindResultCollector {
 void CreateTextFile(const FilePath& filename,
                     const std::wstring& contents) {
   std::ofstream file;
-  file.open(WideToUTF8(filename.ToWStringHack()).c_str());
+  file.open(filename.value().c_str());
   ASSERT_TRUE(file.is_open());
   file << contents;
   file.close();
@@ -173,7 +173,7 @@ void CreateTextFile(const FilePath& filename,
 std::wstring ReadTextFile(const FilePath& filename) {
   wchar_t contents[64];
   std::wifstream file;
-  file.open(WideToUTF8(filename.ToWStringHack()).c_str());
+  file.open(filename.value().c_str());
   EXPECT_TRUE(file.is_open());
   file.getline(contents, 64);
   file.close();