Fix collision calculation

chrome/browser/resources/options/chromeos/display_layout_manager_multi.js

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 cr.exportPath('options');
 
 cr.define('options', function() {
   'use strict';
 
   var DisplayLayoutManager = options.DisplayLayoutManager;
@@ skipping 38 matching lines @@
 
       // Find the closest edge.
       var layoutType = layout.getLayoutTypeForPosition(parent.div, newPosition);
 
       // Calculate the new position and delta.
       var oldPos = {x: layout.div.offsetLeft, y: layout.div.offsetTop};
       var newPos = layout.getSnapPosition(newPosition, parent.div, layoutType);
       var deltaPos = {x: newPos.x - oldPos.x, y: newPos.y - oldPos.y};
 
       // Check for collisions.
-      this.collideAndModifyDelta_(layout, deltaPos);
+      this.collideAndModifyDelta_(layout, oldPos, deltaPos);
       if (deltaPos.x == 0 && deltaPos.y == 0)
         return;
 
       // Update the div (but not the actual layout type or offset yet),
       newPos = {x: oldPos.x + deltaPos.x, y: oldPos.y + deltaPos.y};
       layout.setDivPosition(newPos, parent.div, layoutType);
 
       // If the edge changed, update and highlight it.
       if (layoutType != this.dragLayoutType_ ||
           parentId != this.dragParentId_) {
@@ skipping 117 matching lines @@
 
       // Find the closest edge.
       var layoutType = orphan.getLayoutTypeForPosition(parent.div, pos);
 
       // Snap from the nearest corner to the desired locaiton and get the delta.
       var cornerPos = orphan.getCornerPos(parent.div, pos);
       pos = orphan.getSnapPosition(pos, parent.div, layoutType);
       var deltaPos = {x: pos.x - cornerPos.x, y: pos.y - cornerPos.y};
 
       // Check for collisions.
-      this.collideAndModifyDelta_(orphan, deltaPos);
+      this.collideAndModifyDelta_(orphan, cornerPos, deltaPos);
       pos = {x: cornerPos.x + deltaPos.x, y: cornerPos.y + deltaPos.y};
 
       // Update the div and adjust the corners.
       orphan.layoutType = layoutType;
       orphan.setDivPosition(pos, parent.div, layoutType);
       orphan.adjustCorners(parent.div, layoutType);
 
       // Calculate the bounds from the new div position.
       orphan.calculateOffset(this.visualScale_, parent);
 
@@ skipping 64 matching lines @@
         var delta2 = dx * dx + dy * dy;
         if (closestId == '' || delta2 < closestDelta2) {
           closestId = id;
           closestDelta2 = delta2;
         }
       }
       return closestId;
     },
 
     /**
-     * Intersects |layout| with each other layout and reduces |deltaPos| to
-     * avoid any collisions (or sets it to [0,0] if the div can not be moved
-     * in the direction of |deltaPos|).
+     * Intersects |layout| at |pos| with each other layout and reduces
+     * |deltaPos| to avoid any collisions (or sets it to [0,0] if the div can
+     * not be moved in the direction of |deltaPos|).
      * @param {!options.DisplayLayout} layout
+     * @param {!options.DisplayPosition} pos
      * @param {!options.DisplayPosition} deltaPos
      */
-    collideAndModifyDelta_: function(layout, deltaPos) {
+    collideAndModifyDelta_: function(layout, pos, deltaPos) {
       var keys = Object.keys(
           /** @type {!Object<!options.DisplayLayout>}*/ (
               this.displayLayoutMap_));
       var others = new Set(keys);
       others.delete(layout.id);
       var checkCollisions = true;
       while (checkCollisions) {
         checkCollisions = false;
         for (var tid of others) {
           var tlayout = this.displayLayoutMap_[tid];
-          if (layout.collideWithDivAndModifyDelta(tlayout.div, deltaPos)) {
+          if (layout.collideWithDivAndModifyDelta(pos, tlayout.div, deltaPos)) {
             if (deltaPos.x == 0 && deltaPos.y == 0)
               return;
             others.delete(tid);
             checkCollisions = true;
             break;
           }
         }
       }
     },
 
@@ skipping 48 matching lines @@
       // Parent layout bounds may not be calculated yet, so calculate (but
       // do not set) them.
       var parentBounds = this.calcLayoutBounds_(parent);
       return layout.calculateBounds(parentBounds);
     },
   };
 
   // Export
   return {DisplayLayoutManagerMulti: DisplayLayoutManagerMulti};
 });