Fixed ui::TouchEvent rotation angle out-of-bound issue.

ui/events/gestures/motion_event_aura.cc

Index: ui/events/gestures/motion_event_aura.cc
diff --git a/ui/events/gestures/motion_event_aura.cc b/ui/events/gestures/motion_event_aura.cc
index 1f4d2855b2fc0cfc5d3cd32495f5586d6f6cea13..a6ff09e090182bbd300dd74f11fe9ec91ca4c7b0 100644
--- a/ui/events/gestures/motion_event_aura.cc
+++ b/ui/events/gestures/motion_event_aura.cc
@@ -28,6 +28,14 @@ PointerProperties GetPointerPropertiesFromTouchEvent(const TouchEvent& touch) {
   float radius_x = touch.radius_x();
   float radius_y = touch.radius_y();
   float rotation_angle_rad = touch.rotation_angle() * M_PI / 180.f;
+
+  if (rotation_angle_rad < 0) {

[tdresser, 2015/01/20 13:36:39]

You might want to clarify why you're doing this, and what assumptions you have
about the input.

[mustaq, 2015/01/20 16:26:46]

Done.

+      rotation_angle_rad += M_PI_2;
+      float tmp = radius_x;

[tdresser, 2015/01/20 13:36:39]

Use std::swap.

[mustaq, 2015/01/20 16:26:46]

Done.

+      radius_x = radius_y;
+      radius_y = tmp;
+  }
+
   DCHECK_GE(radius_x, 0) << "Unexpected x-radius < 0";
   DCHECK_GE(radius_y, 0) << "Unexpected y-radius < 0";
   DCHECK(0 <= rotation_angle_rad && rotation_angle_rad <= M_PI_2)