Introduce ui.dll / libui.so for the component build.

ui/gfx/color_utils.h

 // Copyright (c) 2011 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.
 
 #ifndef UI_GFX_COLOR_UTILS_H_
 #define UI_GFX_COLOR_UTILS_H_
 #pragma once
 
 #include "third_party/skia/include/core/SkColor.h"
+#include "ui/ui_api.h"
 
 class SkBitmap;
 
 namespace color_utils {
 
 // Represents an HSL color.
 struct HSL {
   double h;
   double s;
   double l;
 };
 
 unsigned char GetLuminanceForColor(SkColor color);
 
 // Calculated according to http://www.w3.org/TR/WCAG20/#relativeluminancedef
-double RelativeLuminance(SkColor color);
+UI_API double RelativeLuminance(SkColor color);
 
 // Note: these transformations assume sRGB as the source color space
-void SkColorToHSL(SkColor c, HSL* hsl);
-SkColor HSLToSkColor(const HSL& hsl, SkAlpha alpha);
+UI_API void SkColorToHSL(SkColor c, HSL* hsl);
+UI_API SkColor HSLToSkColor(const HSL& hsl, SkAlpha alpha);
 
 // HSL-Shift an SkColor. The shift values are in the range of 0-1, with the
 // option to specify -1 for 'no change'. The shift values are defined as:
 // hsl_shift[0] (hue): The absolute hue value - 0 and 1 map
 //    to 0 and 360 on the hue color wheel (red).
 // hsl_shift[1] (saturation): A saturation shift, with the
 //    following key values:
 //    0 = remove all color.
 //    0.5 = leave unchanged.
 //    1 = fully saturate the image.
 // hsl_shift[2] (lightness): A lightness shift, with the
 //    following key values:
 //    0 = remove all lightness (make all pixels black).
 //    0.5 = leave unchanged.
 //    1 = full lightness (make all pixels white).
-SkColor HSLShift(SkColor color, const HSL& shift);
+UI_API SkColor HSLShift(SkColor color, const HSL& shift);
 
 // Determine if a given alpha value is nearly completely transparent.
 bool IsColorCloseToTransparent(SkAlpha alpha);
 
 // Determine if a color is near grey.
 bool IsColorCloseToGrey(int r, int g, int b);
 
 // Gets a color representing a bitmap. The definition of "representing" is the
 // average color in the bitmap. The color returned is modified to have the
 // specified alpha.
 SkColor GetAverageColorOfFavicon(SkBitmap* bitmap, SkAlpha alpha);
 
 // Builds a histogram based on the Y' of the Y'UV representation of
 // this image.
-void BuildLumaHistogram(SkBitmap* bitmap, int histogram[256]);
+UI_API void BuildLumaHistogram(SkBitmap* bitmap, int histogram[256]);
 
 // Returns a blend of the supplied colors, ranging from |background| (for
 // |alpha| == 0) to |foreground| (for |alpha| == 255). The alpha channels of
 // the supplied colors are also taken into account, so the returned color may
 // be partially transparent.
-SkColor AlphaBlend(SkColor foreground, SkColor background, SkAlpha alpha);
+UI_API SkColor AlphaBlend(SkColor foreground, SkColor background,
+                          SkAlpha alpha);
 
 // Given a foreground and background color, try to return a foreground color
 // that is "readable" over the background color by luma-inverting the foreground
 // color and then picking whichever foreground color has higher contrast against
 // the background color.
 //
 // NOTE: This won't do anything but waste time if the supplied foreground color
 // has a luma value close to the midpoint (0.5 in the HSL representation).
-SkColor GetReadableColor(SkColor foreground, SkColor background);
+UI_API SkColor GetReadableColor(SkColor foreground, SkColor background);
 
 // Gets a Windows system color as a SkColor
-SkColor GetSysSkColor(int which);
+UI_API SkColor GetSysSkColor(int which);
 
 }  // namespace color_utils
 
 #endif  // UI_GFX_COLOR_UTILS_H_