Refactor VR math off of GVR types, onto gfx types where possible.

device/vr/vr_types.h

+// Copyright 2017 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.
+
+#ifndef DEVICE_VR_DEVICE_VR_TYPES_H_

[cjgrant, 2017/04/11 13:44:40]

DEVICE_VR_VR_TYPES_H_

[mthiesse, 2017/04/11 14:46:44]

Done.

+#define DEVICE_VR_DEVICE_VR_TYPES_H_
+
+#include <array>
+
+#include "ui/gfx/geometry/point3_f.h"
+#include "ui/gfx/geometry/point_f.h"
+#include "ui/gfx/geometry/rect.h"
+#include "ui/gfx/geometry/rect_f.h"
+#include "ui/gfx/geometry/size.h"
+#include "ui/gfx/geometry/vector3d_f.h"
+
+namespace vr {
+
+using Matf = std::array<std::array<float, 4>, 4>;

[acondor_, 2017/04/11 15:00:00]

I'd keep the 4 in the name. It makes it clearer that this is not a general
matrix. 

[mthiesse, 2017/04/11 19:21:06]

Done.

+
+typedef struct RotationAxisAngle {
+  float x;
+  float y;
+  float z;
+  float angle;
+} RotationAxisAngle;
+
+typedef struct Colorf {
+  float r;
+  float g;
+  float b;
+  float a;
+} Colorf;
+
+// A floating point quaternion, in JPL format.
+typedef struct Quatf {
+  /// qx, qy, qz are the vector component.
+  float qx;
+  float qy;
+  float qz;
+  /// qw is the linear component.
+  float qw;
+} Quatf;
+
+}  // namespace vr
+
+#endif  // DEVICE_VR_DEVICE_VR_TYPES_H_