ContextMenu Support!

LLContextMenu functionality pulled out of LLPieMenu, PieMenu is now derived from LLContextMenu
- The more attribute boolean of pie_menu element determines whether or not to have an actual submenu if it's not a pie, defaults to false which means actual submenu..
-- in the future we may want to have more more="true" depending on feedback
- Pie menu labels now dynamically get " >" appended to them (avoids stupid looking context menus)
- Positioning logic combined in part, mostly conditional still, in the future we could probably combine it more.
- handleHoverOver function combines common functionality between context and pies given an item and hover mouse coords.

LiruUseContextMenus debug setting determines which to use, default is pie, of course
- Context(/Pie) Menus are rebuilt when the setting changes value
-- this is safe at any point because all startup states have been accounted for
- "Use context menus instead of pie menus" added to System->General preferences (it's close to the bottom)

indra/llui/lluictrlfactory.cpp

@@ -446,7 +446,7 @@ LLMenuGL *LLUICtrlFactory::buildMenu(const std::string &filename, LLView* parent
 //-----------------------------------------------------------------------------
 // buildMenu()
 //-----------------------------------------------------------------------------
-LLPieMenu *LLUICtrlFactory::buildPieMenu(const std::string &filename, LLView* parentp)
+LLContextMenu* LLUICtrlFactory::buildContextMenu(const std::string& filename, LLView* parentp)
 {
 	LLXMLNodePtr root;
 
@@ -465,9 +465,10 @@ LLPieMenu *LLUICtrlFactory::buildPieMenu(const std::string &filename, LLView* pa
 	std::string name("menu");
 	root->getAttributeString("name", name);
 
-	LLPieMenu *menu = new LLPieMenu(name);
+	static LLUICachedControl<bool> context("LiruUseContextMenus", false);
+	LLContextMenu* menu = context ? new LLContextMenu(name) : new LLPieMenu(name);
 	parentp->addChild(menu);
-	menu->initXML(root, parentp, this);
+	menu->initXML(root, parentp, this, context);
 
 	if (LLUI::sShowXUINames)
 	{