Removes ctor's accepting delegates and instead makes them abstract methods, adds some docs

src/Umbraco.Web/BatchedWebServiceServerMessenger.cs

@@ -4,38 +4,44 @@ using Umbraco.Core.Sync;
 
 namespace Umbraco.Web
 {
+    /// <summary>
+    /// An <see cref="IServerMessenger"/> that works by messaging servers via web services.
+    /// </summary>
+    /// <remarks>
+    /// This binds to appropriate umbraco events in order to trigger the FlushBatch() calls
+    /// </remarks>
     internal class BatchedWebServiceServerMessenger : Core.Sync.BatchedWebServiceServerMessenger
     {
         internal BatchedWebServiceServerMessenger()
-            : base(GetBatch)
+            : base()
         {
             UmbracoModule.EndRequest += UmbracoModule_EndRequest;
         }
 
         internal BatchedWebServiceServerMessenger(string login, string password) 
-            : base(login, password, GetBatch)
+            : base(login, password)
         {
             UmbracoModule.EndRequest += UmbracoModule_EndRequest;
         }
 
         internal BatchedWebServiceServerMessenger(string login, string password, bool useDistributedCalls) 
-            : base(login, password, useDistributedCalls, GetBatch)
+            : base(login, password, useDistributedCalls)
         {
             UmbracoModule.EndRequest += UmbracoModule_EndRequest;
         }
 
         public BatchedWebServiceServerMessenger(Func<Tuple<string, string>> getLoginAndPassword)
-            : base(getLoginAndPassword, GetBatch)
+            : base(getLoginAndPassword)
         {
             UmbracoModule.EndRequest += UmbracoModule_EndRequest;
         }
 
-        private static ICollection<RefreshInstructionEnvelope> GetBatch(bool ensure)
+        protected override ICollection<RefreshInstructionEnvelope> GetBatch(bool ensureHttpContext)
         {
             var httpContext = UmbracoContext.Current == null ? null : UmbracoContext.Current.HttpContext;
             if (httpContext == null)
             {
-                if (ensure)
+                if (ensureHttpContext)
                     throw new NotSupportedException("Cannot execute without a valid/current UmbracoContext with an HttpContext assigned.");
                 return null;
             }
@@ -44,7 +50,7 @@ namespace Umbraco.Web
 
             // no thread-safety here because it'll run in only 1 thread (request) at a time
             var batch = (ICollection<RefreshInstructionEnvelope>)httpContext.Items[key];
-            if (batch == null && ensure)
+            if (batch == null && ensureHttpContext)
                 httpContext.Items[key] = batch = new List<RefreshInstructionEnvelope>();
             return batch;
         }