feat(ui): implement Script_CancelRealmListQuery (#109)

Co-authored-by: fallenoak <git@fallenoak.me>

src/glue/CGlueMgr.cpp

@@ -89,6 +89,16 @@ float CalculateAspectRatio() {
     return static_cast<float>(width) / static_cast<float>(height);
 }
 
+void CGlueMgr::CancelRealmListQuery() {
+    if (CGlueMgr::m_idleState != IDLE_REALM_LIST) {
+        return;
+    }
+
+    ClientServices::Connection()->Cancel(2);
+
+    CGlueMgr::SetIdleState(IDLE_NONE);
+}
+
 void CGlueMgr::ChangeRealm(const REALM_INFO* realmInfo) {
     if (!realmInfo) {
         return;

src/glue/CGlueMgr.hpp

@@ -58,6 +58,7 @@ class CGlueMgr {
         static int32_t m_suspended;
 
         // Static functions
+        static void CancelRealmListQuery();
         static void ChangeRealm(const REALM_INFO* realmInfo);
         static void DisplayLoginStatus();
         static void EnterWorld();

src/ui/ScriptFunctionsRealmList.cpp

@@ -19,7 +19,9 @@ int32_t Script_RealmListUpdateRate(lua_State* L) {
 }
 
 int32_t Script_CancelRealmListQuery(lua_State* L) {
-    WHOA_UNIMPLEMENTED(0);
+    CGlueMgr::CancelRealmListQuery();
+
+    return 0;
 }
 
 int32_t Script_GetNumRealms(lua_State* L) {