Detecting and fixing stringprintf.h format bugs

mojo/fetcher/network_fetcher.cc

Index: mojo/fetcher/network_fetcher.cc
diff --git a/mojo/fetcher/network_fetcher.cc b/mojo/fetcher/network_fetcher.cc
index 603cf50de6c42c017227f7e8f6a61e47d0097103..939f1e27e68117fd30db70071814480f9f9012d0 100644
--- a/mojo/fetcher/network_fetcher.cc
+++ b/mojo/fetcher/network_fetcher.cc
@@ -90,8 +90,14 @@ void NetworkFetcher::RecordCacheToURLMapping(const base::FilePath& path,
   base::FilePath map_path = temp_dir.AppendASCII(map_name);
 
   // TODO(eseidel): Paths or URLs with spaces will need quoting.
+#ifdef OS_WIN
+  // FilePath::StringType is std::wstring on Windows
+  std::string map_entry =
+      base::StringPrintf("%ls %s\n", path.value().c_str(), url.spec().c_str());
+#else
   std::string map_entry =
       base::StringPrintf("%s %s\n", path.value().c_str(), url.spec().c_str());
+#endif
   // TODO(eseidel): AppendToFile is missing O_CREAT, crbug.com/450696
   if (!PathExists(map_path)) {
     base::WriteFile(map_path, map_entry.data(),