Reset tapPrevented state on next down

Fixes #1590 Tap event not firing the first time after tracking another element

src/standard/gestures.html

@@ -423,13 +423,16 @@
     },
 
     mousedown: function(e) {
+      POINTERSTATE.tapPrevented = false;
       this.save(e);
     },
+
     click: function(e) {
       this.forward(e);
     },
 
     touchstart: function(e) {
+      POINTERSTATE.tapPrevented = false;
       this.save(e.changedTouches[0]);
     },
     touchend: function(e) {
@@ -450,7 +453,6 @@
           });
         }
       }
-      POINTERSTATE.tapPrevented = false;
       this.reset();
     }
   });