Windows docking should get triggered by pressing against the screen edge

ash/wm/window_util.cc

 // Copyright (c) 2012 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.
 
 #include "ash/wm/window_util.h"
 
 #include <vector>
 
 #include "ash/ash_constants.h"
 #include "ash/root_window_controller.h"
@@ skipping 59 matching lines @@
   return true;
 }
 
 bool CanResizeWindow(const aura::Window* window) {
   return window->GetProperty(aura::client::kCanResizeKey);
 }
 
 bool CanSnapWindow(aura::Window* window) {
   if (!CanResizeWindow(window))
     return false;
+  if (window->type() == aura::client::WINDOW_TYPE_PANEL)
+    return false;
   // If a window has a maximum size defined, snapping may make it too big.
   return window->delegate() ? window->delegate()->GetMaximumSize().IsEmpty() :
                               true;
 }
 
 bool IsWindowNormal(const aura::Window* window) {
   return IsWindowStateNormal(window->GetProperty(aura::client::kShowStateKey));
 }
 
 bool IsWindowStateNormal(ui::WindowShowState state) {
@@ skipping 94 matching lines @@
     return false;
   aura::Window* window_container =
       ash::Shell::GetContainer(target_root, window->parent()->id());
   // Move the window to the target launcher.
   window_container->AddChild(window);
   return true;
 }
 
 }  // namespace wm
 }  // namespace ash