x11: Make sure a Widget is not attempted to be destroyed more than once.

A DesktopWindowTreeHostX11 destroys its children on destruction. So it is
necessary to make sure the Window hasn't already been destroyed with its parent
before attempting to destroy it during app tear-down.

BUG=504692

Review URL: https://codereview.chromium.org/1213103003
TBR=sadrul@ (myself)

Cr-Commit-Position: refs/heads/master@{#336567}
(cherry picked from commit 2a2cfc8f230219e533323b688678187edef7b2ab)

Review URL: https://codereview.chromium.org/1235773007 .

Cr-Commit-Position: refs/branch-heads/2403@{#502}
Cr-Branched-From: f54b8097a9c45ed4ad308133d49f05325d6c5070-refs/heads/master@{#330231}

4 files changed, 42 insertions, 7 deletions

diff --git a/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc b/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
index 69c5b2f..ceffac0 100644
--- a/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
+++ b/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
@@ -237,7 +237,17 @@ void DesktopWindowTreeHostX11::SwapNonClientEventHandler(
   x11_non_client_event_filter_ = handler.Pass();
 }
 
-void DesktopWindowTreeHostX11::CleanUpWindowList() {
+void DesktopWindowTreeHostX11::CleanUpWindowList(
+    void (*func)(aura::Window* window)) {
+  if (!open_windows_)
+    return;
+  while (!open_windows_->empty()) {
+    XID xid = open_windows_->front();
+    func(GetContentWindowForXID(xid));
+    if (!open_windows_->empty() && open_windows_->front() == xid)
+      open_windows_->erase(open_windows_->begin());
+  }
+
   delete open_windows_;
   open_windows_ = NULL;
 }
diff --git a/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h b/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h
index 94d4b1b..59591bd 100644
--- a/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h
+++ b/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h
@@ -83,8 +83,9 @@ class VIEWS_EXPORT DesktopWindowTreeHostX11
   // Swaps the current handler for events in the non client view with |handler|.
   void SwapNonClientEventHandler(scoped_ptr<ui::EventHandler> handler);
 
-  // Deallocates the internal list of open windows.
-  static void CleanUpWindowList();
+  // Runs the |func| callback for each content-window, and deallocates the
+  // internal list of open windows.
+  static void CleanUpWindowList(void (*func)(aura::Window* window));
 
  protected:
   // Overridden from DesktopWindowTreeHost:
diff --git a/ui/views/widget/desktop_aura/desktop_window_tree_host_x11_unittest.cc b/ui/views/widget/desktop_aura/desktop_window_tree_host_x11_unittest.cc
index 17eb63a8..64cb2b7 100644
--- a/ui/views/widget/desktop_aura/desktop_window_tree_host_x11_unittest.cc
+++ b/ui/views/widget/desktop_aura/desktop_window_tree_host_x11_unittest.cc
@@ -456,6 +456,33 @@ TEST_F(DesktopWindowTreeHostX11Test, ToggleMinimizePropogateToContentWindow) {
   EXPECT_TRUE(widget.GetNativeWindow()->IsVisible());
 }
 
+TEST_F(DesktopWindowTreeHostX11Test, ChildWindowDestructionDuringTearDown) {
+  Widget parent_widget;
+  Widget::InitParams parent_params =
+      CreateParams(Widget::InitParams::TYPE_WINDOW);
+  parent_params.ownership = Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
+  parent_params.native_widget = new DesktopNativeWidgetAura(&parent_widget);
+  parent_widget.Init(parent_params);
+  parent_widget.Show();
+  ui::X11EventSource::GetInstance()->DispatchXEvents();
+
+  Widget child_widget;
+  Widget::InitParams child_params =
+      CreateParams(Widget::InitParams::TYPE_WINDOW);
+  child_params.ownership = Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
+  child_params.native_widget = new DesktopNativeWidgetAura(&child_widget);
+  child_params.parent = parent_widget.GetNativeWindow();
+  child_widget.Init(child_params);
+  child_widget.Show();
+  ui::X11EventSource::GetInstance()->DispatchXEvents();
+
+  // Sanity check that the two widgets each have their own XID.
+  ASSERT_NE(parent_widget.GetNativeWindow()->GetHost()->GetAcceleratedWidget(),
+            child_widget.GetNativeWindow()->GetHost()->GetAcceleratedWidget());
+  Widget::CloseAllSecondaryWidgets();
+  EXPECT_TRUE(DesktopWindowTreeHostX11::GetAllOpenWindows().empty());
+}
+
 class MouseEventRecorder : public ui::EventHandler {
  public:
   MouseEventRecorder() {}
diff --git a/ui/views/widget/native_widget_aura.cc b/ui/views/widget/native_widget_aura.cc
index bf113e6..d5bb6df 100644
--- a/ui/views/widget/native_widget_aura.cc
+++ b/ui/views/widget/native_widget_aura.cc
@@ -1060,10 +1060,7 @@ void Widget::CloseAllSecondaryWidgets() {
 #endif
 
 #if defined(USE_X11) && !defined(OS_CHROMEOS)
-  std::vector<aura::Window*> open_windows =
-      DesktopWindowTreeHostX11::GetAllOpenWindows();
-  std::for_each(open_windows.begin(), open_windows.end(), CloseWindow);
-  DesktopWindowTreeHostX11::CleanUpWindowList();
+  DesktopWindowTreeHostX11::CleanUpWindowList(CloseWindow);
 #endif
 }