linux_aura: Fix cursor memeory leak, which was redding the lsan bot.

ui/views/widget/desktop_aura/desktop_native_widget_aura.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 "ui/views/widget/desktop_aura/desktop_native_widget_aura.h"
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "ui/aura/client/activation_client.h"
 #include "ui/aura/client/aura_constants.h"
@@ skipping 192 matching lines @@
 
  private:
   DesktopNativeWidgetAura* desktop_native_widget_aura_;
 
   DISALLOW_COPY_AND_ASSIGN(FocusManagerEventHandler);
 };
 
 ////////////////////////////////////////////////////////////////////////////////
 // DesktopNativeWidgetAura, public:
 
+int DesktopNativeWidgetAura::cursor_reference_count_ = 0;
 DesktopNativeCursorManager* DesktopNativeWidgetAura::native_cursor_manager_ =
     NULL;
 views::corewm::CursorManager* DesktopNativeWidgetAura::cursor_manager_ = NULL;
 
 DesktopNativeWidgetAura::DesktopNativeWidgetAura(
     internal::NativeWidgetDelegate* delegate)
     : ownership_(Widget::InitParams::NATIVE_WIDGET_OWNS_WIDGET),
       close_widget_factory_(this),
       can_activate_(true),
       desktop_root_window_host_(NULL),
@@ skipping 71 matching lines @@
   aura::client::SetFocusClient(root->window(), NULL);
   aura::client::SetActivationClient(root->window(), NULL);
   focus_client_.reset();
 
   aura::client::SetDispatcherClient(root->window(), NULL);
   dispatcher_client_.reset();
 
   aura::client::SetCursorClient(root->window(), NULL);
   native_cursor_manager_->RemoveRootWindow(root);
 
+  cursor_reference_count_--;
+  if (cursor_reference_count_ == 0) {
+    // We are the last DesktopNativeWidgetAura instance, and we are responsible
+    // for cleaning up |cursor_manager_|.
+    delete cursor_manager_;
+    native_cursor_manager_ = NULL;
+    cursor_manager_ = NULL;
+  }

[sadrul, 2014/01/15 22:15:01]

This looks a bit hairy. Perhaps there could be a
[D]CHECK_GE(cursor_reference_count_, 0) here

+
   aura::client::SetScreenPositionClient(root->window(), NULL);
   position_client_.reset();
 
   aura::client::SetDragDropClient(root->window(), NULL);
   drag_drop_client_.reset();
 
   aura::client::SetEventClient(root->window(), NULL);
   event_client_.reset();
 }
 
@@ skipping 76 matching lines @@
   // CEF sets focus to the window the user clicks down on.
   // TODO(beng): see if we can't do this some other way. CEF seems a heavy-
   //             handed way of accomplishing focus.
   // No event filter for aura::Env. Create CompoundEvnetFilter per RootWindow.
   root_window_event_filter_ = new corewm::CompoundEventFilter;
   // Pass ownership of the filter to the root_window.
   root_window_->window()->SetEventFilter(root_window_event_filter_);
 
   // |root_window_| must be added to |native_cursor_manager_| before
   // OnRootWindowCreated() is called.
+  cursor_reference_count_++;
   if (!native_cursor_manager_) {
     native_cursor_manager_ = new DesktopNativeCursorManager(
         DesktopCursorLoaderUpdater::Create());
   }
   if (!cursor_manager_) {
     cursor_manager_ = new views::corewm::CursorManager(
         scoped_ptr<corewm::NativeCursorManager>(native_cursor_manager_));
   }
   native_cursor_manager_->AddRootWindow(root_window_.get());
   aura::client::SetCursorClient(root_window_->window(), cursor_manager_);
@@ skipping 712 matching lines @@
   input_method_event_filter_->SetInputMethodPropertyInRootWindow(
       root_window_->window());
   root_window_event_filter_->AddHandler(input_method_event_filter_.get());
 }
 
 void DesktopNativeWidgetAura::UpdateWindowTransparency() {
   content_window_->SetTransparent(ShouldUseNativeFrame());
 }
 
 }  // namespace views