When there is nothing selected in a media filter list, don't enable its remove button

Also missed xml parts from last commit.

indra/newview/llfloatermediafilter.cpp

@@ -62,6 +62,10 @@ BOOL LLFloaterMediaFilter::postBuild()
 	mBlacklist = getChild<LLScrollListCtrl>("blacklist");
 	updateLists(LLMediaFilter::WHITELIST);
 	updateLists(LLMediaFilter::BLACKLIST);
+	mWhitelist->setCommitOnSelectionChange(true);
+	mBlacklist->setCommitOnSelectionChange(true);
+	mWhitelist->setCommitCallback(boost::bind(&LLFloaterMediaFilter::enableButton, this, getChildView("remove_whitelist"), mWhitelist));
+	mBlacklist->setCommitCallback(boost::bind(&LLFloaterMediaFilter::enableButton, this, getChildView("remove_blacklist"), mBlacklist));
 
 	return TRUE;
 }
@@ -80,6 +84,12 @@ void LLFloaterMediaFilter::updateLists(LLMediaFilter::EMediaList list_type)
 		element["columns"][0]["value"] = (*itr);
 		scroll->addElement(element);
 	}
+	enableButton(getChildView(white ? "remove_whitelist" : "remove_blacklist"), scroll);
+}
+
+void LLFloaterMediaFilter::enableButton(LLView* btn, const LLScrollListCtrl* scroll)
+{
+	btn->setEnabled(!scroll->isEmpty() && scroll->getFirstSelected());
 }
 
 void on_add_to_list(bool white)

indra/newview/llfloatermediafilter.h

@@ -44,6 +44,7 @@ public:
 private:
 	~LLFloaterMediaFilter();
 	void updateLists(LLMediaFilter::EMediaList list);
+	void enableButton(LLView* btn, const LLScrollListCtrl* scroll);
 	void onRemoveFromList(bool white);
 
 	LLScrollListCtrl* mWhitelist;

indra/newview/skins/default/xui/en-us/floater_media_lists.xml

@@ -85,8 +85,8 @@
         mouse_opaque="false"
         name="add_whitelist">
         <button.commit_callback
-         function="MediaFilter.CommitAction"
-         parameter="AddToWhitelist"/>
+         function="MediaFilter.OnAdd"
+         parameter="1"/>
     </button>
 
    </layout_panel>
@@ -112,8 +112,8 @@
         mouse_opaque="false"
         name="remove_whitelist">
         <button.commit_callback
-         function="MediaFilter.CommitAction"
-         parameter="RemoveFromWhitelist"/>
+         function="MediaFilter.OnRemove"
+         parameter="1"/>
     </button>
 
     </layout_panel>
@@ -176,8 +176,7 @@
         mouse_opaque="false"
         name="add_blacklist">
         <button.commit_callback
-         function="MediaFilter.CommitAction"
-         parameter="AddToBlacklist"/>
+         function="MediaFilter.OnAdd"/>
     </button>
 
     </layout_panel>
@@ -203,8 +202,7 @@
         mouse_opaque="false"
         name="remove_blacklist">
         <button.commit_callback
-         function="MediaFilter.CommitAction"
-         parameter="RemoveFromBlacklist"/>
+         function="MediaFilter.OnRemove"/>
     </button>
 
     </layout_panel>