Use a more correct conversion to uint8_t.

ui/gfx/color_utils.cc

 // Copyright (c) 2012 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.
 
 #include "ui/gfx/color_utils.h"
 
 #include <stdint.h>
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/logging.h"
 #include "base/numerics/safe_conversions.h"
 #include "build/build_config.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/gfx/color_palette.h"
+#include "ui/gfx/geometry/safe_integer_conversions.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include "skia/ext/skia_utils_win.h"
 #endif
 
 namespace color_utils {
 
 
 // Helper functions -----------------------------------------------------------
@@ skipping 100 matching lines @@
 }
 
 SkColor HSLToSkColor(const HSL& hsl, SkAlpha alpha) {
   double hue = hsl.h;
   double saturation = hsl.s;
   double lightness = hsl.l;
 
   // If there's no color, we don't care about hue and can do everything based on
   // brightness.
   if (!saturation) {
-    uint8_t light;
-
-    if (lightness < 0)
-      light = 0;
-    else if (lightness >= 1.0)
-      light = 255;
-    else
-      light = static_cast<uint8_t>(SkDoubleToFixed(lightness) >> 8);
-
+    const uint8_t light =
+        base::saturated_cast<uint8_t>(gfx::ToRoundedInt(lightness * 255));
     return SkColorSetARGB(alpha, light, light, light);
   }
 
   double temp2 = (lightness < 0.5) ?
       (lightness * (1.0 + saturation)) :
       (lightness + saturation - (lightness * saturation));
   double temp1 = 2.0 * lightness - temp2;
   return SkColorSetARGB(alpha, calcHue(temp1, temp2, hue + 1.0 / 3.0),
                         calcHue(temp1, temp2, hue),
                         calcHue(temp1, temp2, hue - 1.0 / 3.0));
@@ skipping 180 matching lines @@
   if (IsDark(text_color)) {
     // For black text, this comes out to kChromeIconGrey.
     return color_utils::AlphaBlend(SK_ColorWHITE, text_color,
                                    SkColorGetR(gfx::kChromeIconGrey));
   }
   // The dimming is less dramatic when darkening a light color.
   return color_utils::AlphaBlend(SK_ColorBLACK, text_color, 0x33);
 }
 
 }  // namespace color_utils