network applet: fixes to # of visible networks (#12417)

* network applet: fix accounting of menu indexes

In _createSection() and _createNetworkItem(), previously we would skip
the menu index in which the active network is present.  If this index
was < NUM_VISIBLE_NETWORKS, then we could display too few networks
before we begin stashing them in the "more" menu.

_accessPointAdded() is also refactored to more closely resemble the
above two, but this is a nonbehavioral change.

* network applet: keep visible networks under limit

When adding a network, if we add it to a menu index <
NUM_VISIBLE_NETWORKS, if we now have > NUM_VISIBLE_NETWORKS networks, we
need to push the last visible network to being the first network in the
"more" menu.  Otherwise, we could end up with too many visible networks.

When updating a network position, we first removed it from the menu.
When doing this, if its original menu index was < NUM_VISIBLE_NETWORKS,
then we need to bump the first network in the "more" menu to being the
last visible network.  We now do this by now calling the already
existing _accessPointRemoved() method which handles this case.
Otherwise, we could end up with too few visible networks.

files/usr/share/cinnamon/applets/network@cinnamon.org/applet.js

@@ -603,8 +603,10 @@ NMDevice.prototype = {
             for(let j = 0; j < this._connections.length; ++j) {
                 let obj = this._connections[j];
                 if (this._activeConnection &&
-                    obj.connection == this._activeConnection.connection)
+                    obj.connection == this._activeConnection.connection) {
+                    activeOffset = 0; // we no longer need to account for this
                     continue;
+                }
                 obj.item = this._createConnectionItem(obj);
 
                 if (j + activeOffset >= NUM_VISIBLE_NETWORKS) {
@@ -1383,8 +1385,7 @@ NMDeviceWireless.prototype = {
         }
 
         if (needsupdate) {
-            if (apObj.item)
-                apObj.item.destroy();
+            this._accessPointRemoved(device, accessPoint);
 
             if (pos != -1)
                 this._networks.splice(pos, 1);
@@ -1398,7 +1399,7 @@ NMDeviceWireless.prototype = {
             }
 
             // skip networks that should appear earlier
-            let menuPos = 0;
+            let menuPos = this._activeConnectionItem ? 1 : 0;
             for (pos = 0;
                  pos < this._networks.length &&
                  this._networkSortFunction(this._networks[pos], apObj) < 0; ++pos) {
@@ -1410,8 +1411,20 @@ NMDeviceWireless.prototype = {
             this._networks.splice(pos, 0, apObj);
 
             if (this._shouldShowConnectionList()) {
-                menuPos += (this._activeConnectionItem ? 1 : 0);
                 this._createNetworkItem(apObj, menuPos);
+                if (menuPos < NUM_VISIBLE_NETWORKS && this._networks.length > NUM_VISIBLE_NETWORKS) {
+                    for (; menuPos < NUM_VISIBLE_NETWORKS; ++pos) {
+                        if (this._networks[pos] != this._activeNetwork)
+                            menuPos++;
+                    }
+                    let item = this._networks[pos].item;
+                    if (item && item._apObj) {
+                        item.destroy();
+                        item._apObj.item = null;
+
+                        this._createNetworkItem(item._apObj, NUM_VISIBLE_NETWORKS);
+                    }
+                }
             }
         }
     },
@@ -1703,8 +1716,10 @@ NMDeviceWireless.prototype = {
 
         for(let j = 0; j < this._networks.length; j++) {
             let apObj = this._networks[j];
-            if (apObj == this._activeNetwork)
+            if (apObj == this._activeNetwork) {
+                activeOffset = 0; // we no longer need to account for this
                 continue;
+            }
 
             this._createNetworkItem(apObj, j + activeOffset);
         }