aura: Fix a couple of drag drop issues:

ash/drag_drop/drag_drop_controller.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/drag_drop/drag_drop_controller.h"
 
 #include "ash/drag_drop/drag_image_view.h"
 #include "ash/shell.h"
 #include "ash/wm/cursor_manager.h"
 #include "base/message_loop.h"
@@ skipping 14 matching lines @@
 #include "ui/views/widget/native_widget_aura.h"
 
 namespace ash {
 namespace internal {
 
 using aura::RootWindow;
 
 namespace {
 const base::TimeDelta kDragDropAnimationDuration =
     base::TimeDelta::FromMilliseconds(250);
+
+void UnlockAndSwitchCursor(gfx::NativeCursor new_cursor) {
+  ash::Shell::GetInstance()->cursor_manager()->UnlockCursor();

[sky, 2012/08/02 16:26:42]

Unlock/Lock decrement/increment a count. So, it's entirely possible this won't
set the cursor.

[varunjain, 2012/08/02 17:29:52]

I have moved the cursor locking to the RootWindow.
I wish there was some nicer way to use the cursor manager's locking
functionality :(
Do you have any other idea?

+  ash::Shell::GetInstance()->cursor_manager()->SetCursor(new_cursor);
+  ash::Shell::GetInstance()->cursor_manager()->LockCursor();
+}
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 // DragDropController, public:
 
 DragDropController::DragDropController()
     : drag_image_(NULL),
       drag_data_(NULL),
       drag_operation_(0),
       drag_window_(NULL),
@@ skipping 12 matching lines @@
 int DragDropController::StartDragAndDrop(const ui::OSExchangeData& data,
                                          const gfx::Point& root_location,
                                          int operation) {
   DCHECK(!drag_drop_in_progress_);
   // TODO(oshima): Add CaptureClient client API.
   aura::Window* capture_window =
       aura::client::GetCaptureWindow(Shell::GetPrimaryRootWindow());
   if (capture_window)
     capture_window->ReleaseCapture();
   drag_drop_in_progress_ = true;
+  ash::Shell::GetInstance()->cursor_manager()->LockCursor();
 
   drag_data_ = &data;
   drag_operation_ = operation;
   const ui::OSExchangeDataProviderAura& provider =
       static_cast<const ui::OSExchangeDataProviderAura&>(data.provider());
 
   drag_image_.reset(new DragImageView);
   drag_image_->SetImage(provider.drag_image());
   drag_image_offset_ = provider.drag_image_offset();
   drag_image_->SetBoundsInScreen(gfx::Rect(
@@ skipping 44 matching lines @@
                               drag_operation_);
       e.set_flags(event.flags());
       int op = delegate->OnDragUpdated(e);
       gfx::NativeCursor cursor = ui::kCursorNoDrop;
       if (op & ui::DragDropTypes::DRAG_COPY)
         cursor = ui::kCursorCopy;
       else if (op & ui::DragDropTypes::DRAG_LINK)
         cursor = ui::kCursorAlias;
       else if (op & ui::DragDropTypes::DRAG_MOVE)
         cursor = ui::kCursorMove;
-      ash::Shell::GetInstance()->cursor_manager()->SetCursor(cursor);
+      UnlockAndSwitchCursor(cursor);
     }
   }
 
   DCHECK(drag_image_.get());
   if (drag_image_->visible()) {
     drag_image_->SetScreenPosition(
         event.root_location().Subtract(drag_image_offset_));
   }
 }
 
 void DragDropController::Drop(aura::Window* target,
                               const aura::LocatedEvent& event) {
-  ash::Shell::GetInstance()->cursor_manager()->SetCursor(ui::kCursorPointer);
+  UnlockAndSwitchCursor(ui::kCursorPointer);
   aura::client::DragDropDelegate* delegate = NULL;
 
   // We must guarantee that a target gets a OnDragEntered before Drop. WebKit
   // depends on not getting a Drop without DragEnter. This behavior is
   // consistent with drag/drop on other platforms.
   if (target != drag_window_)
     DragUpdate(target, event);
   DCHECK(target == drag_window_);
 
   if ((delegate = aura::client::GetDragDropDelegate(target))) {
     aura::DropTargetEvent e(
         *drag_data_, event.location(), event.root_location(), drag_operation_);
     e.set_flags(event.flags());
     drag_operation_ = delegate->OnPerformDrop(e);
     if (drag_operation_ == 0)
       StartCanceledAnimation();
     else
       drag_image_.reset();
   } else {
     drag_image_.reset();
   }
 
   Cleanup();
   if (should_block_during_drag_drop_)
     quit_closure_.Run();
 }
 
 void DragDropController::DragCancel() {
-  ash::Shell::GetInstance()->cursor_manager()->SetCursor(ui::kCursorPointer);
+  UnlockAndSwitchCursor(ui::kCursorPointer);
 
   // |drag_window_| can be NULL if we have just started the drag and have not
   // received any DragUpdates, or, if the |drag_window_| gets destroyed during
   // a drag/drop.
   aura::client::DragDropDelegate* delegate = drag_window_?
       aura::client::GetDragDropDelegate(drag_window_) : NULL;
   if (delegate)
     delegate->OnDragExited();
 
   Cleanup();
@@ skipping 20 matching lines @@
                                              aura::MouseEvent* event) {
   if (!drag_drop_in_progress_)
     return false;
   switch (event->type()) {
     case ui::ET_MOUSE_DRAGGED:
       DragUpdate(target, *event);
       break;
     case ui::ET_MOUSE_RELEASED:
       Drop(target, *event);
       break;
-    case ui::ET_MOUSE_EXITED:
-      DragCancel();
-      break;
     default:
       // We could reach here if the user drops outside the root window.
       // We could also reach here because RootWindow may sometimes generate a
       // bunch of fake mouse events
       // (aura::RootWindow::PostMouseMoveEventAfterWindowChange).
       break;
   }
   return true;
 }
 
@@ skipping 58 matching lines @@
   animation_setter.AddObserver(this);
   window->SetBounds(gfx::Rect(drag_start_location_, window->bounds().size()));
 }
 
 void DragDropController::Cleanup() {
   if (drag_window_)
     drag_window_->RemoveObserver(this);
   drag_window_ = NULL;
   drag_data_ = NULL;
   drag_drop_in_progress_ = false;
+  if (ash::Shell::GetInstance()->cursor_manager()->is_cursor_locked())
+    ash::Shell::GetInstance()->cursor_manager()->UnlockCursor();
 }
 
 }  // namespace internal
 }  // namespace ash