Only allow pointer events on children of active layers.

This allows multiple active layers to work together.  Before, the
topmost active layer will receive all pointer events.

This also fixes an issue in the sceneObject exit function (it should
clear the parent, not delete the parent function).  This, in turn,
required a fix to the annotation test because the test map is destroyed
between tests.

src/main.styl

@@ -32,7 +32,8 @@
     height 100%
     pointer-events none
     &.active
-      pointer-events auto
+      > *
+        pointer-events auto
 
   .geo-tile-layer
     transform-origin 0px 0px

src/sceneObject.js

@@ -179,7 +179,7 @@ var sceneObject = function (arg) {
    */
   this._exit = function () {
     m_children = [];
-    delete m_this.parent;
+    m_parent = null;
     s_exit();
   };
 

tests/cases/annotation.js

@@ -151,6 +151,10 @@ describe('geo.annotation', function () {
       expect(ann.layer()).toBe(layer);
     });
     it('state', function () {
+      map = createMap();
+      layer = map.createLayer('annotation', {
+        annotations: geo.listAnnotations()
+      });
       var ann = geo.annotation.annotation('test', {layer: layer});
       map.geoOn(geo.event.annotation.state, function (evt) {
         stateEvent += 1;

tests/cases/widget.js

@@ -249,4 +249,26 @@ describe('widget api', function () {
     domWidget._exit();
     expect($(o.uiLayer.canvas()).children().length).toBe(widgetCount - 1);
   });
+  it('widgets on two layers should both be clickable', function () {
+    var o = makeMap(),
+        offset = o.map.node().offset(),
+        uiLayer2 = o.map.createLayer('ui'),
+        clickCount = 0, clickCount2 = 0,
+        widget = o.uiLayer.createWidget('dom', {
+          position: {top: 0, left: 0, width: '20px', height: '20px'}
+        }),
+        widget2 = uiLayer2.createWidget('dom', {
+          position: {top: 0, left: 30, width: '20px', height: '20px'}
+        });
+    $(widget.canvas()).on('click', function () {
+      clickCount += 1;
+    });
+    $(widget2.canvas()).on('click', function () {
+      clickCount2 += 1;
+    });
+    document.elementFromPoint(offset.left + 10, offset.top + 10).click();
+    document.elementFromPoint(offset.left + 40, offset.top + 10).click();
+    expect(clickCount).toBe(1);
+    expect(clickCount2).toBe(1);
+  });
 });