EXT-8577 WIP Context menu items for multi-attachments.

Done:
- 1. Dropped the obsolete "MultipleAttachments" setting.
- 2. Added an "Add" item to the following attachment-related context menus:
     * My Appearance (ex-My Outfits) context menu.
     * Edit Outfit -> Add More context menu.
     * Object in-world context menu.
     * Inventory context menu.
     * Object inspector gear menu.
- 3. Modified "Attach To / Attach To HUD" to perform the "add" instead of "replace" action.

TODO:
- Ability to attach multiple objects at once from the Add More panel (bulk attach).
- Make sure there's no memleak when you click Wear/Attach in the in-world object context menu
  and the callback isn't invoked (because e.g. avatar fails to get close enough to the object).

Issues:

0. I'm not sure whether LLAgentWearables::userAttachMultipleAttachments()
   should replace attachments or add them. Assumed the former.

1. I couldn't verify that adding objects from the object inspector menu works
   because I either could wear an object or see its inspector, not both.

2. > 1. Right-click on an object in your inventory and select "Wear".
   > VERIFY: Attaches the object and replaces whatever's there; asks for
   > confirmation before replacing an existing object.
   I think this is impossible to implement because we don't know in advance
   what point the object will be attached to, so we can't display a confirmation dialog.

Reviewed by Seraph at https://codereview.productengine.com/secondlife/r/843/

--HG--
branch : product-engine

1 files changed, 6 insertions, 3 deletions

diff --git a/indra/newview/llselectmgr.cpp b/indra/newview/llselectmgr.cpp
index 050b87bbe0..21f8485e90 100644
--- a/indra/newview/llselectmgr.cpp
+++ b/indra/newview/llselectmgr.cpp
@@ -3615,7 +3615,7 @@ void LLSelectMgr::selectionSetObjectSaleInfo(const LLSaleInfo& sale_info)
 // Attachments
 //----------------------------------------------------------------------
 
-void LLSelectMgr::sendAttach(U8 attachment_point)
+void LLSelectMgr::sendAttach(U8 attachment_point, bool replace)
 {
 	LLViewerObject* attach_object = mSelectedObjects->getFirstRootObject();
 
@@ -3629,9 +3629,12 @@ void LLSelectMgr::sendAttach(U8 attachment_point)
 	if (0 == attachment_point ||
 		get_if_there(gAgentAvatarp->mAttachmentPoints, (S32)attachment_point, (LLViewerJointAttachment*)NULL))
 	{
-
-		if (gSavedSettings.getBOOL("MultipleAttachments"))
+		if (!replace || attachment_point != 0)
+		{
+			// If we know the attachment point then we got here by clicking an
+			// "Attach to..." context menu item, so we should add, not replace.
 			attachment_point |= ATTACHMENT_ADD;
+		}
 
 		sendListToRegions(
 			"ObjectAttach",