[windows] Make most file_win.cc functions use malloc for string conversions.

runtime/bin/socket_win.cc

Index: runtime/bin/socket_win.cc
diff --git a/runtime/bin/socket_win.cc b/runtime/bin/socket_win.cc
index f76f764c7c4835789c8fda0024d216c3b34778b7..1dce52e9d974554fe9ad00e1a6e89bbb8aac37c6 100644
--- a/runtime/bin/socket_win.cc
+++ b/runtime/bin/socket_win.cc
@@ -370,12 +370,12 @@ bool Socket::ReverseLookup(const RawAddr& addr,
 
 bool Socket::ParseAddress(int type, const char* address, RawAddr* addr) {
   int result;
-  const wchar_t* system_address = StringUtilsWin::Utf8ToWide(address);
+  Utf8ToWideScope system_address(address);
   if (type == SocketAddress::TYPE_IPV4) {
-    result = InetPton(AF_INET, system_address, &addr->in.sin_addr);
+    result = InetPton(AF_INET, system_address.wide(), &addr->in.sin_addr);
   } else {
     ASSERT(type == SocketAddress::TYPE_IPV6);
-    result = InetPton(AF_INET6, system_address, &addr->in6.sin6_addr);
+    result = InetPton(AF_INET6, system_address.wide(), &addr->in6.sin6_addr);
   }
   return result == 1;
 }