make tests portable by using 565 compatible colors

gm/addarc.cpp

 /*
  * Copyright 2015 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 "SkAnimTimer.h"
 #include "SkCanvas.h"
@@ skipping 18 matching lines @@
         paint.setAntiAlias(true);
         paint.setStyle(SkPaint::kStroke_Style);
         paint.setStrokeWidth(15);
 
         const SkScalar inset = paint.getStrokeWidth() + 4;
         const SkScalar sweepAngle = 345;
         SkRandom rand;
 
         SkScalar sign = 1;
         while (r.width() > paint.getStrokeWidth() * 3) {
-            paint.setColor(rand.nextU() | (0xFF << 24));
+            paint.setColor(sk_tool_utils::color_to_565(rand.nextU() | (0xFF << 24)));
             SkScalar startAngle = rand.nextUScalar1() * 360;
 
             SkScalar speed = SkScalarSqrt(16 / r.width()) * 0.5f;
             startAngle += fRotate * 360 * speed * sign;
 
             SkPath path;
             path.addArc(r, startAngle, sweepAngle);
             canvas->drawPath(path, paint);
 
             r.inset(inset, inset);
@@ skipping 87 matching lines @@
 
         const SkScalar delta = paint.getStrokeWidth() * 3 / 2;
         SkRect r = SkRect::MakeXYWH(-12, -12, 24, 24);
         SkRandom rand;
 
         SkScalar sign = 1;
         while (r.width() > paint.getStrokeWidth() * 2) {
             SkAutoCanvasRestore acr(canvas, true);
             canvas->rotate(fRotate * sign);
 
-            paint.setColor(rand.nextU() | (0xFF << 24));
+            paint.setColor(sk_tool_utils::color_to_565(rand.nextU() | (0xFF << 24)));
             canvas->drawOval(r, paint);
             r.inset(delta, delta);
             sign = -sign;
         }
     }
 
     bool onAnimate(const SkAnimTimer& timer) override {
         fRotate = timer.scaled(60, 360);
         return true;
     }
@@ skipping 66 matching lines @@
             canvas->restore();
             canvas->translate(0, 40);
         }
     }
     
 private:
     typedef skiagm::GM INHERITED;
 };
 DEF_GM( return new ManyArcsGM; )