Sync with obsidian in attempt to fix SV-2086

Applies MAINT-4897 FIXED Frequent error when texturing a linkset - "Unable to add texture. Please wait a few seconds and try again."
Applies MAINT-5547 FIXED errors when texturing a linkset "Unable to add texture. Please wait a few seconds and try again."

indra/newview/lltooldraganddrop.cpp

@@ -976,11 +976,14 @@ BOOL LLToolDragAndDrop::handleDropTextureProtections(LLViewerObject* hit_obj,
 		return TRUE;
 	}
 
-	// In case the inventory has not been updated (e.g. due to some recent operation
-	// causing a dirty inventory), stall the user while fetching the inventory.
-	if (hit_obj->isInventoryDirty())
-	{
-		hit_obj->fetchInventoryFromServer();
+	// In case the inventory has not been loaded (e.g. due to some recent operation
+	// causing a dirty inventory) and we can do an update, stall the user
+	// while fetching the inventory.
+	//
+	// Fetch if inventory is dirty and listener is present (otherwise we will not receive update)
+	if (hit_obj->isInventoryDirty() && hit_obj->hasInventoryListeners())
+	{
+		hit_obj->requestInventory();
 		LLSD args;
 		args["ERROR_MESSAGE"] = "Unable to add texture.\nPlease wait a few seconds and try again.";
 		LLNotificationsUtil::add("ErrorMessage", args);
@@ -1060,10 +1063,12 @@ BOOL LLToolDragAndDrop::handleDropTextureProtections(LLViewerObject* hit_obj,
 		{
 			hit_obj->updateInventory(new_item, TASK_INVENTORY_ITEM_KEY, true);
 		}
-		// Force the object to update its refetch its inventory so it has this texture.
-		hit_obj->fetchInventoryFromServer();
+		// Force the object to update and refetch its inventory so it has this texture.
+		hit_obj->dirtyInventory();
+		hit_obj->requestInventory();
  		// TODO: Check to see if adding the item was successful; if not, then
-		// we should return false here.
+		// we should return false here. This will requre a separate listener
+		// since without listener, we have no way to receive update
 	}
 	return TRUE;
 }

indra/newview/llviewerobject.cpp

@@ -2594,22 +2594,32 @@ void LLViewerObject::clearInventoryListeners()
 	mInventoryCallbacks.clear();
 }
 
+bool LLViewerObject::hasInventoryListeners()
+{
+	return !mInventoryCallbacks.empty();
+}
+
 void LLViewerObject::requestInventory()
 {
 	if(mInventoryDirty && mInventory && !mInventoryCallbacks.empty())
 	{
 		mInventory->clear(); // will deref and delete entries
 		delete mInventory;
 		mInventory = NULL;
-		mInventoryDirty = FALSE; //since we are going to request it now
 	}
+
 	if(mInventory)
 	{
+		// inventory is either up to date or doesn't has a listener
+		// if it is dirty, leave it this way in case we gain a listener
 		doInventoryCallback();
 	}
-	// throw away duplicate requests
 	else
 	{
+		// since we are going to request it now
+		mInventoryDirty = FALSE;
+
+		// Note: throws away duplicate requests
 		fetchInventoryFromServer();
 	}
 }
@@ -2619,8 +2629,6 @@ void LLViewerObject::fetchInventoryFromServer()
 	if (!mInventoryPending)
 	{
 		delete mInventory;
-		mInventory = NULL;
-		mInventoryDirty = FALSE;
 		LLMessageSystem* msg = gMessageSystem;
 		msg->newMessageFast(_PREHASH_RequestTaskInventory);
 		msg->nextBlockFast(_PREHASH_AgentData);

indra/newview/llviewerobject.h

@@ -54,27 +54,27 @@ class LLAgent;			// TODO: Get rid of this.
 class LLAudioSource;
 class LLAudioSourceVO;
 class LLBBox;
-class LLDataPacker;
 class LLColor4;
-class LLFrameTimer;
+class LLDataPacker;
 class LLDrawable;
+class LLFrameTimer;
 class LLHost;
-class LLWorld;
+class LLMessageSystem;
 class LLNameValue;
 class LLNetMap;
-class LLMessageSystem;
 class LLPartSysData;
-class LLPrimitive;
 class LLPipeline;
+class LLPrimitive;
 class LLTextureEntry;
-class LLViewerTexture;
+class LLVOAvatar;
+class LLVOInventoryListener;
 class LLViewerInventoryItem;
 class LLViewerObject;
+class LLViewerObjectMedia;
 class LLViewerPartSourceScript;
 class LLViewerRegion;
-class LLViewerObjectMedia;
-class LLVOInventoryListener;
-class LLVOAvatar;
+class LLViewerTexture;
+class LLWorld;
 
 typedef enum e_object_update_type
 {
@@ -112,7 +112,7 @@ struct PotentialReturnableObject
 
 //============================================================================
 
-class LLViewerObject : public LLPrimitive, public LLRefCount, public LLGLUpdate
+class LLViewerObject: public LLPrimitive, public LLRefCount, public LLGLUpdate
 {
 protected:
 	~LLViewerObject(); // use unref()
@@ -446,8 +446,8 @@ class LLViewerObject : public LLPrimitive, public LLRefCount, public LLGLUpdate
 	void removeInventoryListener(LLVOInventoryListener* listener);
 	BOOL isInventoryPending() { return mInventoryPending; }
 	void clearInventoryListeners();
+	bool hasInventoryListeners();
 	void requestInventory();
-	void fetchInventoryFromServer();
 	static void processTaskInv(LLMessageSystem* msg, void** user_data);
 	void removeInventory(const LLUUID& item_id);
 
@@ -595,6 +595,9 @@ class LLViewerObject : public LLPrimitive, public LLRefCount, public LLGLUpdate
 	// Motion prediction between updates
 	void interpolateLinearMotion(const F64SecondsImplicit & time, const F32SecondsImplicit & dt);
 
+	// forms task inventory request if none are pending
+	void fetchInventoryFromServer();
+
 public:
 	//
 	// Viewer-side only types - use the LL_PCODE_APP mask.