Revert of Simple cleanups related to SkFixed.

include/core/SkFixed.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkFixed_DEFINED
 #define SkFixed_DEFINED
 
 #include "SkTypes.h"
 
 /** \file SkFixed.h
 
     Types and macros for 16.16 fixed point
 */
 
 /** 32 bit signed integer used to represent fractions values with 16 bits to the right of the decimal point
 */
 typedef int32_t             SkFixed;
 #define SK_Fixed1           (1 << 16)
 #define SK_FixedHalf        (1 << 15)
 #define SK_FixedMax         (0x7FFFFFFF)
 #define SK_FixedMin         (-SK_FixedMax)
+#define SK_FixedNaN         ((int) 0x80000000)
 #define SK_FixedPI          (0x3243F)
 #define SK_FixedSqrt2       (92682)
 #define SK_FixedTanPIOver8  (0x6A0A)
 #define SK_FixedRoot2Over2  (0xB505)
 
 #define SkFixedToFloat(x)   ((x) * 1.52587890625e-5f)
 #if 1
     #define SkFloatToFixed(x)   ((SkFixed)((x) * SK_Fixed1))
 #else
     // pins over/under flows to max/min int32 (slower than just a cast)
@@ skipping 126 matching lines @@
 #define Sk48Dot16FloorToInt(x)    static_cast<int>((x) >> 16)
 
 static inline float Sk48Dot16ToScalar(Sk48Dot16 x) {
     return static_cast<float>(x * 1.5258789e-5);  // x * (1.0f / (1 << 16))
 }
 #define SkFloatTo48Dot16(x)       (static_cast<Sk48Dot16>((x) * (1 << 16)))
 
 #define SkScalarTo48Dot16(x)      SkFloatTo48Dot16(x)
 
 #endif