Merge "don't attempt to normalize the rotation vector" into gingerbread

        float qx = sqrtf( clamp( Hx - My - Az + 1) * 0.25f );

        float qy = sqrtf( clamp(-Hx + My - Az + 1) * 0.25f );

        float qz = sqrtf( clamp(-Hx - My + Az + 1) * 0.25f );

        const float n = 1.0f / (qw*qw + qx*qx + qy*qy + qz*qz);

        qx = copysignf(qx, Ay - Mz) * n;

        qy = copysignf(qy, Hz - Ax) * n;

        qz = copysignf(qz, Mx - Hy) * n;

        qx = copysignf(qx, Ay - Mz);

        qy = copysignf(qy, Hz - Ax);

        qz = copysignf(qz, Mx - Hy);

        // this quaternion is guaranteed to be normalized, by construction

        // of the rotation matrix.

        *outEvent = event;

        outEvent->data[0] = qx;