Make QML overlays disappear, use fade for non-window types

interface/resources/qml/desktop/Desktop.qml

@@ -268,24 +268,45 @@ FocusScope {
         pinned = newPinned
     }
 
-    onPinnedChanged: {
+    property real unpinnedAlpha: 1.0;
 
+    Behavior on unpinnedAlpha {
+        NumberAnimation {
+            easing.type: Easing.Linear;
+            duration: 300
+        }
+    }
+
+    state: "NORMAL"
+    states: [
+        State {
+            name: "NORMAL"
+            PropertyChanges { target: desktop; unpinnedAlpha: 1.0 }
+        },
+        State {
+            name: "PINNED"
+            PropertyChanges { target: desktop; unpinnedAlpha: 0.0 }
+        }
+    ]
+
+    transitions: [
+        Transition {
+             NumberAnimation { properties: "unpinnedAlpha"; duration: 300 }
+        }
+    ]
+
+    onPinnedChanged: {
         if (pinned) {
+            // recalculate our non-pinned children
             hiddenChildren = d.findMatchingChildren(desktop, function(child){
                 return !d.isTopLevelWindow(child) && child.visible;
             });
 
             hiddenChildren.forEach(function(child){
-                child.visible = false;
+                child.opacity = Qt.binding(function(){ return desktop.unpinnedAlpha });
             });
-        } else {
-            hiddenChildren.forEach(function(child){
-                if (child) {
-                    child.visible = true;
-                }
-            });
-            hiddenChildren = [];
         }
+        state = pinned ? "PINNED" : "NORMAL"
     }
 
     onShowDesktop: pinned = false

interface/resources/qml/windows/ModalWindow.qml

@@ -16,7 +16,7 @@ Window {
     id: window
     modality: Qt.ApplicationModal
     destroyOnCloseButton: true
-    destroyOnInvisible: true
+    destroyOnHidden: true
     frame: ModalFrame { }
 
     property int colorScheme: hifi.colorSchemes.light

scripts/system/libraries/toolBars.js

@@ -256,7 +256,7 @@ ToolBar = function(x, y, direction, optionalPersistenceKey, optionalInitialPosit
                 y: y - ToolBar.SPACING
             });
         }
-        this.save();
+        //this.save();
     }
 
     this.setAlpha = function(alpha, tool) {