Ignore update cursor messages from blink when the cursor position lies outside our root window

content/browser/renderer_host/render_widget_host_view_aura.cc

Index: content/browser/renderer_host/render_widget_host_view_aura.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.cc b/content/browser/renderer_host/render_widget_host_view_aura.cc
index 77ea38814b5068f6f561e17d9c9e858b5cc6243a..1d952656bf56e9222a7778e55eeb38504283123c 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.cc
+++ b/content/browser/renderer_host/render_widget_host_view_aura.cc
@@ -2471,8 +2471,10 @@ void RenderWidgetHostViewAura::UpdateCursorIfOverSelf() {
   if (!root_window)
     return;
 
-  gfx::Point root_window_point =
+  gfx::Point cursor_screen_point =
       gfx::Screen::GetScreenFor(GetNativeView())->GetCursorScreenPoint();
+
+  gfx::Point root_window_point = cursor_screen_point;
   aura::client::ScreenPositionClient* screen_position_client =
       aura::client::GetScreenPositionClient(root_window);
   if (screen_position_client) {
@@ -2483,6 +2485,23 @@ void RenderWidgetHostViewAura::UpdateCursorIfOverSelf() {
   if (root_window->GetEventHandlerForPoint(root_window_point) != window_)
     return;
 
+#if defined(OS_WIN)
+  // We can receive SetCursor messages from blink even when we are not the
+  // foreground window. This can happen for e.g. when the dev tools window
+  // is updating styles etc. We only want the cursor update to occur on
+  // the portion of the window outside the foreground window.
+  if (legacy_render_widget_host_HWND_) {

[scottmg, 2015/11/11 05:37:52]

Couldn't this happen when the legacy hwnd is disabled too?

[ananta, 2015/11/11 19:35:08]

The legacy window is disabled only for metro mode and by a command line switch.
We are using the legacy window as a signal that this is not metro mode.

+    HWND focus_window = ::GetFocus();
+    if (focus_window != GetNativeView()->GetHost()->GetAcceleratedWidget()) {
+      RECT focus_window_screen_rect = {0};
+      ::GetWindowRect(focus_window, &focus_window_screen_rect);
+      // The cursor is within the bounds of another window. Ignore.
+      if (::PtInRect(&focus_window_screen_rect, cursor_screen_point.ToPOINT()))
+        return;
+    }
+  }
+#endif
+
   gfx::NativeCursor cursor = current_cursor_.GetNativeCursor();
   // Do not show loading cursor when the cursor is currently hidden.
   if (is_loading_ && cursor != ui::kCursorNone)