Release aura::Desktop event handler windows on detaching an ancestor window.

ui/aura/desktop.cc

 // Copyright (c) 2011 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 "ui/aura/desktop.h"
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 82 matching lines @@
 
 void GetEventFiltersToNotify(Window* target, EventFilters* filters) {
   Window* window = target->parent();
   while (window) {
     if (window->event_filter())
       filters->push_back(window->event_filter());
     window = window->parent();
   }
 }
 
+// Returns true if |descendant| is a descendant of |ancestor|.
+bool IsAncestor(Window* ancestor, Window* descendant) {
+  while (descendant && descendant != ancestor)
+    descendant = descendant->parent();
+  return descendant == ancestor;

[Ben Goodger (Google), 2011/11/28 17:50:19]

Rather than defining this here, can you add a Contains() method to Window,
similar to Layer's?

[flackr, 2011/11/28 20:36:35]

Done.

+}
+
 }  // namespace
 
 Desktop* Desktop::instance_ = NULL;
 bool Desktop::use_fullscreen_host_window_ = false;
 
 ////////////////////////////////////////////////////////////////////////////////
 // Desktop, public:
 
 // static
 Desktop* Desktop::GetInstance() {
@@ skipping 413 matching lines @@
 
 Desktop* Desktop::GetDesktop() {
   return this;
 }
 
 void Desktop::WindowDetachedFromDesktop(Window* detached) {
   DCHECK(capture_window_ != this);
 
   // If the ancestor of the capture window is detached,
   // release the capture.
-  aura::Window* window = capture_window_;
-  while (window && window != detached)
-    window = window->parent();
-  if (window && window != this)
+  if (IsAncestor(detached, capture_window_) && capture_window_ != this)

[sky, 2011/11/28 17:20:22]

Is the capture_window_ condition necessary? Also, see the DCHECK @ 539.

[flackr, 2011/11/28 20:36:35]

Oops, seems like I converted the old statement incorrectly. In the old code,
after the loop window is either NULL or equal to detached so I should check that
detached != this. Done.

     ReleaseCapture(capture_window_);
 
-  // If the ancestor of the capture window is detached,
+  // If the ancestor of the focused window is detached,
   // release the focus.
-  window = focused_window_;
-  while (window && window != detached)
-    window = window->parent();
-  if (window)
+  if (IsAncestor(detached, focused_window_))
     SetFocusedWindow(NULL);
+
+  // If the ancestor of any event handler windows are detached, release the
+  // pointer to those windows.
+  if (IsAncestor(detached, mouse_pressed_handler_))
+    mouse_pressed_handler_ = NULL;
+  if (IsAncestor(detached, mouse_moved_handler_))
+    mouse_moved_handler_ = NULL;
+  if (IsAncestor(detached, touch_event_handler_))
+    touch_event_handler_ = NULL;
 }
 
 void Desktop::OnLayerAnimationEnded(
     const ui::LayerAnimationSequence* animation) {
   OnHostResized(host_->GetSize());
 }
 
 void Desktop::OnLayerAnimationScheduled(
     const ui::LayerAnimationSequence* animation) {
 }
@@ skipping 43 matching lines @@
       base::StringToInt(parts[1], &parsed_height) && parsed_height > 0) {
     bounds.set_size(gfx::Size(parsed_width, parsed_height));
   } else if (use_fullscreen_host_window_) {
     bounds = gfx::Rect(DesktopHost::GetNativeDisplaySize());
   }
 
   return bounds;
 }
 
 }  // namespace aura