Add some syntactic sugar to closures.

src/core/closure.cpp

@@ -63,3 +63,9 @@ void Closure::Cleanup() {
   disconnect();
   deleteLater();
 }
+
+Closure* NewClosure(
+    QObject* sender, const char* signal,
+    QObject* receiver, const char* slot) {
+  return new Closure(sender, signal, receiver, slot);
+}

src/core/closure.h

@@ -73,4 +73,35 @@ class Closure : public QObject {
 
 #define C_ARG(type, data) new ClosureArgument<type>(data)
 
+Closure* NewClosure(
+    QObject* sender,
+    const char* signal,
+    QObject* receiver,
+    const char* slot);
+
+template <typename T>
+Closure* NewClosure(
+    QObject* sender,
+    const char* signal,
+    QObject* receiver,
+    const char* slot,
+    const T& val0) {
+  return new Closure(
+      sender, signal, receiver, slot,
+      C_ARG(T, val0));
+}
+
+template <typename T0, typename T1>
+Closure* NewClosure(
+    QObject* sender,
+    const char* signal,
+    QObject* receiver,
+    const char* slot,
+    const T0& val0,
+    const T1& val1) {
+  return new Closure(
+      sender, signal, receiver, slot,
+      C_ARG(T0, val0), C_ARG(T1, val1));
+}
+
 #endif  // CLOSURE_H

src/internet/groovesharkservice.cpp

@@ -173,10 +173,9 @@ int GroovesharkService::SearchAlbums(const QString& query) {
 
   const int id = next_pending_search_id_++;
 
-  new Closure(reply, SIGNAL(finished()),
-              this, SLOT(SearchAlbumsFinished(QNetworkReply*,int)),
-              C_ARG(QNetworkReply*, reply),
-              C_ARG(int, id));
+  NewClosure(reply, SIGNAL(finished()),
+             this, SLOT(SearchAlbumsFinished(QNetworkReply*,int)),
+             reply, id);
 
   return id;
 }
@@ -222,10 +221,9 @@ void GroovesharkService::FetchSongsForAlbum(int id, quint64 album_id) {
              << Param("country", "");
 
   QNetworkReply* reply = CreateRequest("getAlbumSongs", parameters, false);
-  new Closure(reply, SIGNAL(finished()),
-              this, SLOT(GetAlbumSongsFinished(QNetworkReply*,int)),
-              C_ARG(QNetworkReply*, reply),
-              C_ARG(int, id));
+  NewClosure(reply, SIGNAL(finished()),
+             this, SLOT(GetAlbumSongsFinished(QNetworkReply*,int)),
+             reply, id);
 }
 
 void GroovesharkService::GetAlbumSongsFinished(