path: Use string_view_t consistently

[dexonsmith]

Summary

Most of filesystem/path.cpp uses string_view_t. This fixes the two spots that use string_view directly.

[EricWF]

Thanks!

[dexonsmith]

Fixed in r305661.

libcxx/src/experimental/filesystem/path.cpp

while (P != End && *P != '/')
       P += Inc;
     return P;
   }
 };
 
 string_view_pair separate_filename(string_view_t const & s) {
     if (s == "." || s == ".." || s.empty()) return string_view_pair{s, ""};
     auto pos = s.find_last_of('.');
-    if (pos == string_view_t::npos) return string_view_pair{s, string_view{}};
+    if (pos == string_view_t::npos)
+        return string_view_pair{s, string_view_t{}};
     return string_view_pair{s.substr(0, pos), s.substr(pos)};
 }
 
 string_view_t createView(PosPtr S, PosPtr E) noexcept {
   return {S, static_cast<size_t>(E - S) + 1};
 }
 
 }} // namespace parser
int path::__compare(string_view_t __s) const {
     return 1;
 }
 
 ////////////////////////////////////////////////////////////////////////////
 // path.nonmembers
 size_t hash_value(const path& __p) noexcept {
   auto PP = PathParser::CreateBegin(__p.native());
   size_t hash_value = 0;
-  std::hash<string_view> hasher;
+  std::hash<string_view_t> hasher;
   while (PP) {
     hash_value = __hash_combine(hash_value, hasher(*PP));
     ++PP;
   }
   return hash_value;
 }
 
 ////////////////////////////////////////////////////////////////////////////