From 4ceaaf5ea1ab6d7565a4c5d3212a0d7875a401a4 Mon Sep 17 00:00:00 2001
From: epriestley <git@epriestley.com>
Date: Sat, 24 Jan 2015 14:18:33 -0800
Subject: [PATCH] Allow scrollbars to be dragged outside the window on
 supporting browsers

Summary: In Safari, Firefox and Chrome drags outside the window will work if we do this. Safari didn't work before, not sure about the other two.

Test Plan: Clicked the scroll handle, then dragged my mouse to the right (outside the window) and down. Page scrolled in Safari, Firefox, and Chrome.

Reviewers: btrahan, chad

Reviewed By: chad

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D11484
---
 resources/celerity/map.php                      | 16 ++++++++--------
 webroot/rsrc/externals/javelin/lib/Scrollbar.js |  6 +++++-
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/resources/celerity/map.php b/resources/celerity/map.php
index 0dce05bfcc..5e3976ecca 100644
--- a/resources/celerity/map.php
+++ b/resources/celerity/map.php
@@ -199,7 +199,7 @@ return array(
     'rsrc/externals/javelin/lib/Resource.js' => '44959b73',
     'rsrc/externals/javelin/lib/Routable.js' => 'b3e7d692',
     'rsrc/externals/javelin/lib/Router.js' => '29274e2b',
-    'rsrc/externals/javelin/lib/Scrollbar.js' => '65a65098',
+    'rsrc/externals/javelin/lib/Scrollbar.js' => 'a89e4fc3',
     'rsrc/externals/javelin/lib/URI.js' => '6eff08aa',
     'rsrc/externals/javelin/lib/Vector.js' => 'cc1bd0b0',
     'rsrc/externals/javelin/lib/WebSocket.js' => '3f840822',
@@ -673,7 +673,7 @@ return array(
     'javelin-resource' => '44959b73',
     'javelin-routable' => 'b3e7d692',
     'javelin-router' => '29274e2b',
-    'javelin-scrollbar' => '65a65098',
+    'javelin-scrollbar' => 'a89e4fc3',
     'javelin-stratcom' => '8b0ad945',
     'javelin-tokenizer' => '7644823e',
     'javelin-typeahead' => '70baed2f',
@@ -1244,12 +1244,6 @@ return array(
       'javelin-dom',
       'javelin-fx',
     ),
-    '65a65098' => array(
-      'javelin-install',
-      'javelin-dom',
-      'javelin-stratcom',
-      'javelin-vector',
-    ),
     '6882e80a' => array(
       'javelin-dom',
     ),
@@ -1556,6 +1550,12 @@ return array(
       'javelin-stratcom',
       'javelin-dom',
     ),
+    'a89e4fc3' => array(
+      'javelin-install',
+      'javelin-dom',
+      'javelin-stratcom',
+      'javelin-vector',
+    ),
     'a8d8459d' => array(
       'javelin-behavior',
       'javelin-dom',
diff --git a/webroot/rsrc/externals/javelin/lib/Scrollbar.js b/webroot/rsrc/externals/javelin/lib/Scrollbar.js
index b8e643b484..f80c65dd43 100644
--- a/webroot/rsrc/externals/javelin/lib/Scrollbar.js
+++ b/webroot/rsrc/externals/javelin/lib/Scrollbar.js
@@ -76,7 +76,11 @@ JX.install('Scrollbar', {
     JX.DOM.listen(this._bar, 'mousedown', null, JX.bind(this, this._onjump));
 
     JX.enableDispatch(document.body, 'mouseenter');
-    JX.enableDispatch(document.body, 'mousemove');
+
+    // Enabling dispatch for this event on `window` allows us to scroll even
+    // if the mouse cursor is dragged outside the window in at least some
+    // browsers (for example, Safari on OSX).
+    JX.enableDispatch(window, 'mousemove');
 
     JX.DOM.listen(viewport, 'mouseenter', null, JX.bind(this, this._onenter));
     JX.DOM.listen(frame, 'scroll', null, JX.bind(this, this._onscroll));