make tests portable by using 565 compatible colors

gm/colorcube.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 #include "SkColorCubeFilter.h"
 #include "SkBitmapSource.h"
@@ skipping 67 matching lines @@
         uint8_t* lut = (uint8_t*)lutMemory.get();
         uint8_t* invLut = (uint8_t*)invLutMemory.get();
         const int maxIndex = size - 1;
         for (int i = 0; i < size; i++) {
             lut[i] = (i * 255) / maxIndex;
             invLut[i] = ((maxIndex - i) * 255) / maxIndex;
         }
         for (int r = 0; r < size; ++r) {
             for (int g = 0; g < size; ++g) {
                 for (int b = 0; b < size; ++b) {
-                    pixels[(size * ((size * b) + g)) + r] = SkColorSetARGB(0xFF,
+                    pixels[(size * ((size * b) + g)) + r] = sk_tool_utils::color_to_565(
+                            SkColorSetARGB(0xFF,
                             invR ? invLut[r] : lut[r],
                             invG ? invLut[g] : lut[g],
-                            invB ? invLut[b] : lut[b]);
+                            invB ? invLut[b] : lut[b]));
                 }
             }
         }
     }
 
     virtual SkISize onISize() {
         return SkISize::Make(500, 100);
     }
 
     virtual void onDraw(SkCanvas* canvas) {
@@ skipping 30 matching lines @@
     SkData* f3DLut32;
     SkData* f3DLut64;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 static GM* MyFactory(void*) { return new ColorCubeGM; }
 static GMRegistry reg(MyFactory);
 
 }