Convert native mouse locations to the locations in screen coordinate in RootWindowHostLinux.

ash/wm/workspace/workspace_window_resizer.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/workspace/workspace_window_resizer.h"
 
 #include <algorithm>
 #include <cmath>
 #include <utility>
 #include <vector>
@@ skipping 104 matching lines @@
 WorkspaceWindowResizer* WorkspaceWindowResizer::Create(
     aura::Window* window,
     const gfx::Point& location_in_parent,
     int window_component,
     const std::vector<aura::Window*>& attached_windows) {
   Details details(window, location_in_parent, window_component);
   return details.is_resizable ?
       new WorkspaceWindowResizer(details, attached_windows) : NULL;
 }
 
-void WorkspaceWindowResizer::Drag(const gfx::Point& location, int event_flags) {
-  std::pair<aura::RootWindow*, gfx::Point> actual_location =
-      wm::GetRootWindowRelativeToWindow(window()->parent(), location);
-  aura::RootWindow* current_root = actual_location.first;
-  gfx::Point location_in_parent = actual_location.second;
-  aura::Window::ConvertPointToTarget(current_root,
-                                     window()->parent(),
-                                     &location_in_parent);
+void WorkspaceWindowResizer::Drag(const gfx::Point& location_in_parent,
+                                  int event_flags) {
   last_mouse_location_ = location_in_parent;
 
-  // Do not use |location| below this point, use |location_in_parent| instead.
-  // When the pointer is on |window()->GetRootWindow()|, |location| and
-  // |location_in_parent| have the same value and both of them are in
-  // |window()->parent()|'s coordinates, but once the pointer enters the
-  // other root window, you will see an unexpected value on the former. See
-  // comments in wm::GetRootWindowRelativeToWindow() for details.
-
   int grid_size = event_flags & ui::EF_CONTROL_DOWN ? 0 : kScreenEdgeInset;
   gfx::Rect bounds =  // in |window()->parent()|'s coordinates.
       CalculateBoundsForDrag(details_, location_in_parent);
 
   if (wm::IsWindowNormal(window()))
     AdjustBoundsForMainWindow(&bounds, grid_size);
 
   if (bounds != window()->bounds()) {
     if (!did_move_or_resize_) {
       if (!details_.restore_bounds.IsEmpty())
         ClearRestoreBounds(window());
       RestackWindows();
     }
     did_move_or_resize_ = true;
   }
 
-  const bool in_original_root = (window()->GetRootWindow() == current_root);
+  gfx::Point location_in_screen = location_in_parent;
+  wm::ConvertPointToScreen(window()->parent(), &location_in_screen);
+  const bool in_original_root =
+      wm::GetRootWindowAt(location_in_screen) == window()->GetRootWindow();
   // Hide a phantom window for snapping if the cursor is in another root window.
   if (in_original_root) {
     UpdateSnapPhantomWindow(location_in_parent, bounds);
   } else {
     snap_type_ = SNAP_NONE;
     snap_phantom_window_controller_.reset();
   }
 
   if (!attached_windows_.empty())
     LayoutAttachedWindows(bounds);
@@ skipping 486 matching lines @@
   gfx::Rect layer_bounds = layer_->bounds();
   layer_bounds.set_origin(gfx::Point(0, 0));
   layer_->SetBounds(layer_bounds);
   layer_->SetVisible(false);
   // Detach it from the current container.
   layer_->parent()->Remove(layer_);
 }
 
 }  // namespace internal
 }  // namespace ash