exo: Fix cursor scale when crossing displays

components/exo/pointer.cc

Index: components/exo/pointer.cc
diff --git a/components/exo/pointer.cc b/components/exo/pointer.cc
index 62fbcb3d8dfaf27f4da2a360eef3e9ece01703e3..df906c9bef2c07793a45ef13eed3cb996ab05408 100644
--- a/components/exo/pointer.cc
+++ b/components/exo/pointer.cc
@@ -265,6 +265,13 @@ void Pointer::OnCursorDisplayChanging(const display::Display& display) {
   auto info = helper->GetDisplayInfo(display.id());
   display_scale_ = info.GetEffectiveUIScale() * info.device_scale_factor();
   device_scale_factor_ = display.device_scale_factor();
+
+  if (focus_ && surface_) {
+    // Capture is asynchronous, so avoid rendering old cursor in the meantime.

[reveman, 2017/04/28 21:37:09]

I'm still not convinced that we should do this. One cursor transition instead of
two seems better imo. I would hate to see the cursor flicker. Much better to
show an incorrectly sized cursor for a few ms imo. How about just a simple
CaptureCursor() call here for now so we can land this fix and you can then file
a bug for the incorrect size problem and use that bug to convince me that
showing no cursor for a few ms is better. Is that OK?

[oshima, 2017/05/01 22:18:04]

Yes, we need a better way to handle custom cursors in general.
(high contract, large cursors are others)

Let me file a bug(s).

I agree that it's probably better to not to reset to none, but i'll leave it to
you guys.

[Dominik Laskowski, 2017/05/06 00:34:45]

Done, and filed a bug: http://crbug.com/719116

+    cursor_capture_weak_ptr_factory_.InvalidateWeakPtrs();
+    UpdateCursor(ui::CursorType::kNone);
+    CaptureCursor();
+  }
 }
 
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