From 53037d475af3908487141c1d4762d8aece38b281 Mon Sep 17 00:00:00 2001
From: Daniel Freedman <dfreedm@google.com>
Date: Wed, 29 Jul 2015 11:56:36 -0700
Subject: [PATCH] Deduplicate track/untrack document event listener logic

---
 src/standard/gestures.html | 52 +++++++++++++++-----------------------
 1 file changed, 20 insertions(+), 32 deletions(-)

diff --git a/src/standard/gestures.html b/src/standard/gestures.html
index ed721f334f..b0fdc3f1dc 100644
--- a/src/standard/gestures.html
+++ b/src/standard/gestures.html
@@ -137,6 +137,18 @@
     return ta;
   }
 
+  function trackDocument(stateObj, movefn, upfn) {
+    stateObj.movefn = movefn;
+    stateObj.upfn = upfn;
+    document.addEventListener('mousemove', movefn);
+    document.addEventListener('mouseup', upfn);
+  }
+
+  function untrackDocument(stateObj) {
+    document.removeEventListener('mousemove', stateObj.movefn);
+    document.removeEventListener('mouseup', stateObj.upfn);
+  }
+
   var Gestures = {
     gestures: {},
     recognizers: [],
@@ -381,19 +393,7 @@
     },
 
     reset: function() {
-      this.untrackDocument();
-    },
-
-    trackDocument: function(movefn, upfn) {
-      this.info.movefn = movefn;
-      this.info.upfn = upfn;
-      document.addEventListener('mousemove', movefn);
-      document.addEventListener('mouseup', upfn);
-    },
-
-    untrackDocument: function() {
-      document.removeEventListener('mousemove', this.info.movefn);
-      document.removeEventListener('mouseup', this.info.upfn);
+      untrackDocument(this.info);
     },
 
     mousedown: function(e) {
@@ -405,16 +405,16 @@
       var movefn = function movefn(e) {
         if (!hasLeftMouseButton(e)) {
           self.fire('up', t, e);
-          self.untrackDocument();
+          untrackDocument(self.info);
         }
       };
       var upfn = function upfn(e) {
         if (hasLeftMouseButton(e)) {
           self.fire('up', t, e);
         }
-        self.untrackDocument();
+        untrackDocument(self.info);
       };
-      this.trackDocument(movefn, upfn);
+      trackDocument(this.info, movefn, upfn);
       this.fire('down', t, e);
     },
     touchstart: function(e) {
@@ -461,18 +461,6 @@
       prevent: false
     },
 
-    trackDocument: function(movefn, upfn) {
-      this.info.movefn = movefn;
-      this.info.upfn = upfn;
-      document.addEventListener('mousemove', movefn);
-      document.addEventListener('mouseup', upfn);
-    },
-
-    untrackDocument: function() {
-      document.removeEventListener('mousemove', this.info.movefn);
-      document.removeEventListener('mouseup', this.info.upfn);
-    },
-
     reset: function() {
       this.info.state = 'start';
       this.info.started = false;
@@ -480,7 +468,7 @@
       this.info.x = 0;
       this.info.y = 0;
       this.info.prevent = false;
-      this.untrackDocument();
+      untrackDocument(this.info);
     },
 
     hasMovedEnough: function(x, y) {
@@ -510,7 +498,7 @@
           if (!hasLeftMouseButton(e)) {
             // always fire "end"
             self.info.state = 'end';
-            self.untrackDocument();
+            untrackDocument(self.info);
           }
           self.fire(t, e);
           self.info.started = true;
@@ -523,10 +511,10 @@
         }
 
         // remove the temporary listeners
-        self.untrackDocument();
+        untrackDocument(self.info);
       };
       // add temporary document listeners as mouse retargets
-      this.trackDocument(movefn, upfn);
+      trackDocument(this.info, movefn, upfn);
       this.info.x = e.clientX;
       this.info.y = e.clientY;
     },