Automated g4 rollback of changelist 111522388.

*** Reason for rollback ***

Bringing original changes back

*** Original change description ***

Automated g4 rollback of changelist 111352260.

*** Reason for rollback ***

Breaks Gmail

*** Original change description ***

Allow further propagation of `mousedown` event for draggable elements.

There is currently an issue when default mousedown event gets cancelled for
draggable elements.
Consider an example when you have a draggable div with some
input inside. If you click on input, it won't get focus and you won't be able
to type anything, because focus is a default ev...

***
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=111525196

closure/goog/fx/abstractdragdrop.js

@@ -1404,8 +1404,6 @@ goog.fx.DragDropItem.prototype.maybeStartDrag_ = function(event, element) {
 
   this.startPosition_ = new goog.math.Coordinate(
       event.clientX, event.clientY);
-
-  event.preventDefault();
 };
 
 
@@ -1432,6 +1430,9 @@ goog.fx.DragDropItem.prototype.mouseMove_ = function(event) {
     this.eventHandler_.removeAll();
     this.parent_.startDrag(event, this);
   }
+
+  // Prevent text selection while dragging an element.
+  event.preventDefault();
 };
 
 

closure/goog/fx/abstractdragdrop_test.js

@@ -26,6 +26,7 @@ goog.require('goog.math.Box');
 goog.require('goog.math.Coordinate');
 goog.require('goog.style');
 goog.require('goog.testing.events');
+goog.require('goog.testing.events.Event');
 goog.require('goog.testing.jsunit');
 
 var targets = [
@@ -507,6 +508,22 @@ function testScrollableContainersCalculation() {
   assertEquals(container, group.targetList_[1].scrollableContainer_);
 }
 
+function testMouseDownEventDefaultAction() {
+  var group = new goog.fx.AbstractDragDrop();
+  var target = new goog.fx.AbstractDragDrop();
+  group.addTarget(target);
+  var item1 = new goog.fx.DragDropItem(document.getElementById('child1'));
+  group.items_.push(item1);
+  item1.setParent(group);
+  group.init();
+
+  var mousedownDefaultPrevented =
+      !goog.testing.events.fireMouseDownEvent(item1.element);
+
+  assertFalse('Default action of mousedown event should not be cancelled.',
+      mousedownDefaultPrevented);
+}
+
 // See http://b/7494613.
 function testMouseUpOutsideElement() {
   var group = new goog.fx.AbstractDragDrop();
@@ -583,14 +600,20 @@ function testMouseMove_mouseOutBeforeThreshold() {
     draggedItem = item;
   };
 
-  var event = {'clientX': 8, 'clientY': 10, // Drag distance is only 2
-    'type': goog.events.EventType.MOUSEOUT, 'target': childEl};
+  var event = new goog.testing.events.Event(goog.events.EventType.MOUSEOUT,
+      childEl);
+  // Drag distance is only 2.
+  event.clientX = 8;
+  event.clientY = 10;
   item.mouseMove_(event);
   assertEquals('DragStart should not be fired for mouseout on child element.',
       null, draggedItem);
 
-  var event = {'clientX': 8, 'clientY': 10, // Drag distance is only 2
-    'type': goog.events.EventType.MOUSEOUT, 'target': itemEl};
+  var event = new goog.testing.events.Event(goog.events.EventType.MOUSEOUT,
+      itemEl);
+  // Drag distance is only 2.
+  event.clientX = 8;
+  event.clientY = 10;
   item.mouseMove_(event);
   assertEquals('DragStart should be fired for mouseout on main element.',
       item, draggedItem);