Manually compute inverted matrix for screen rotation

ui/base/events/event.cc

Index: ui/base/events/event.cc
diff --git a/ui/base/events/event.cc b/ui/base/events/event.cc
index 288eab9de0b75236a9db82cc4846596d7343d183..552699e04ff8d287640c652ff3efef4a51ee4106 100644
--- a/ui/base/events/event.cc
+++ b/ui/base/events/event.cc
@@ -268,13 +268,10 @@ LocatedEvent::LocatedEvent(EventType type,
 }
 
 void LocatedEvent::UpdateForRootTransform(
-    const gfx::Transform& root_transform) {
+    const gfx::Transform& reversed_root_transform) {
   // Transform has to be done at root level.
   gfx::Point3F p(location_);
-  root_transform.TransformPointReverse(p);
-  // TODO(oshima): Translating a point using reversed matrix can
-  // results in small error like 0 -> -0.01, whose floored value
-  // is -1 instead of 0. crbug.com/222483.
+  reversed_root_transform.TransformPoint(p);
   root_location_ = location_ = gfx::ToFlooredPoint(p.AsPointF());
 }