some js warning fixes. r=bienvenu.

mailnews/base/resources/content/commandglue.js

@@ -541,6 +541,7 @@ function SortFolderPane(column, sortKey)
 	//Remove the sortActive attribute because we don't want this pane to have any
 	//sort styles.
 	node.setAttribute("sortActive", "false");
+	return true;
 }
 
 function SortColumn(node, sortKey, secondarySortKey, direction)
@@ -814,8 +815,8 @@ function GetNextMessageAfterDelete(messages)
 	if(!nextMessage)
 	{
 
-		var curMessage = messages[0];
-		var nextMessage = null;
+		curMessage = messages[0];
+		nextMessage = null;
 		//search forward
 		while(curMessage)
 		{

mailnews/base/resources/content/mail3PaneWindowCommands.js

@@ -315,6 +315,7 @@ var DefaultController =
 			default:
 				return false;
 		}
+		return false;
 	},
 
 	doCommand: function(command)

mailnews/base/resources/content/msgMail3PaneWindow.js

@@ -352,7 +352,7 @@ function loadStartFolder(startFolderUri)
 			if(!inboxFolder) return;
 
 			var resource = inboxFolder.QueryInterface(Components.interfaces.nsIRDFResource);
-			var startFolderUri = resource.Value;
+			startFolderUri = resource.Value;
 
 			//first, let's see if it's already in the dom.  This will make life easier.
 			//We need to make sure content is built by this time
@@ -478,6 +478,8 @@ function FindInSidebar(currentWindow, id)
 		if(frameItem)
 			return frameItem;
 	}
+
+	return null;
 }
 
 function GetThreadAndMessagePaneSplitter()
@@ -569,19 +571,6 @@ function GetSelectedFolder()
 
 }
 
-function GetSelectedMessage()
-{
-	var tree = GetThreadTree();
-	var selection = tree.selectedItems;
-	if(selection.length > 0)
-		return selection[0];
-	else
-		return null;
-
-}
-
-
-
 function GetServer(uri)
 {
     if (!uri) return null;