Remove member variables from NativeTheme.

These three colors are never set to non-default values, so hard-code
them in the only place where they're used (NativeThemeBase).

Bug: none
Change-Id: I0c3d8ee2efd0f5fd428917341dadc54c1a3f958d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1642271Reviewed-by: Leonard Grey <lgrey@chromium.org>
Commit-Queue: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#666004}

ui/native_theme/native_theme.cc

@@ -22,14 +22,6 @@ NativeTheme::ExtraParams::ExtraParams(const ExtraParams& other) {
   memcpy(this, &other, sizeof(*this));
 }
 
-void NativeTheme::SetScrollbarColors(unsigned inactive_color,
-                                     unsigned active_color,
-                                     unsigned track_color) {
-  thumb_inactive_color_ = inactive_color;
-  thumb_active_color_ = active_color;
-  track_color_ = track_color;
-}
-
 void NativeTheme::AddObserver(NativeThemeObserver* observer) {
   native_theme_observers_.AddObserver(observer);
 }
@@ -44,10 +36,7 @@ void NativeTheme::NotifyObservers() {
 }
 
 NativeTheme::NativeTheme()
-    : thumb_inactive_color_(0xeaeaea),
-      thumb_active_color_(0xf4f4f4),
-      track_color_(0xd3d3d3),
-      is_dark_mode_(IsForcedDarkMode()),
+    : is_dark_mode_(IsForcedDarkMode()),
       is_high_contrast_(IsForcedHighContrast()) {}
 
 NativeTheme::~NativeTheme() {

ui/native_theme/native_theme.h

@@ -284,11 +284,6 @@ class NATIVE_THEME_EXPORT NativeTheme {
   // when the part is resized.
   virtual gfx::Rect GetNinePatchAperture(Part part) const = 0;
 
-  // Supports theme specific colors.
-  void SetScrollbarColors(unsigned inactive_color,
-                          unsigned active_color,
-                          unsigned track_color);
-
   // Colors for GetSystemColor().
   enum ColorId {
     // Windows
@@ -441,10 +436,6 @@ class NATIVE_THEME_EXPORT NativeTheme {
     is_high_contrast_ = is_high_contrast;
   }
 
-  unsigned int thumb_inactive_color_;
-  unsigned int thumb_active_color_;
-  unsigned int track_color_;
-
  private:
   // DarkModeObserver callback.
   void OnParentDarkModeChanged(bool is_dark_mode);

ui/native_theme/native_theme_base.cc

@@ -36,6 +36,10 @@ const int kCheckboxAndRadioHeight = 13;
 const int kSliderThumbWidth = 11;
 const int kSliderThumbHeight = 21;
 
+constexpr SkColor kThumbActiveColor = SkColorSetRGB(0xF4, 0xF4, 0xF4);
+constexpr SkColor kThumbInactiveColor = SkColorSetRGB(0xEA, 0xEA, 0xEA);
+constexpr SkColor kTrackColor = SkColorSetRGB(0xD3, 0xD3, 0xD3);
+
 const SkColor kSliderTrackBackgroundColor =
     SkColorSetRGB(0xe3, 0xdd, 0xd8);
 const SkColor kSliderThumbLightGrey = SkColorSetRGB(0xf4, 0xf2, 0xef);
@@ -280,7 +284,7 @@ void NativeThemeBase::PaintArrowButton(cc::PaintCanvas* canvas,
 
   // Calculate button color.
   SkScalar trackHSV[3];
-  SkColorToHSV(track_color_, trackHSV);
+  SkColorToHSV(kTrackColor, trackHSV);
   SkColor buttonColor = SaturateAndBrighten(trackHSV, 0, 0.2f);
   SkColor backgroundColor = buttonColor;
   if (state == kPressed) {
@@ -347,7 +351,7 @@ void NativeThemeBase::PaintArrowButton(cc::PaintCanvas* canvas,
   flags.setAntiAlias(true);
   flags.setStyle(cc::PaintFlags::kStroke_Style);
   SkScalar thumbHSV[3];
-  SkColorToHSV(thumb_inactive_color_, thumbHSV);
+  SkColorToHSV(kThumbInactiveColor, thumbHSV);
   flags.setColor(OutlineColor(trackHSV, thumbHSV));
   canvas->drawPath(outline, flags);
 
@@ -422,12 +426,12 @@ void NativeThemeBase::PaintScrollbarTrack(
 
   skrect.set(rect.x(), rect.y(), rect.right(), rect.bottom());
   SkScalar track_hsv[3];
-  SkColorToHSV(track_color_, track_hsv);
+  SkColorToHSV(kTrackColor, track_hsv);
   flags.setColor(SaturateAndBrighten(track_hsv, 0, 0));
   canvas->drawIRect(skrect, flags);
 
   SkScalar thumb_hsv[3];
-  SkColorToHSV(thumb_inactive_color_, thumb_hsv);
+  SkColorToHSV(kThumbInactiveColor, thumb_hsv);
 
   flags.setColor(OutlineColor(track_hsv, thumb_hsv));
   DrawBox(canvas, rect, flags);
@@ -444,7 +448,7 @@ void NativeThemeBase::PaintScrollbarThumb(cc::PaintCanvas* canvas,
   const bool vertical = part == kScrollbarVerticalThumb;
 
   SkScalar thumb[3];
-  SkColorToHSV(hovered ? thumb_active_color_ : thumb_inactive_color_, thumb);
+  SkColorToHSV(hovered ? kThumbActiveColor : kThumbInactiveColor, thumb);
 
   cc::PaintFlags flags;
   flags.setColor(SaturateAndBrighten(thumb, 0, 0.02f));
@@ -470,7 +474,7 @@ void NativeThemeBase::PaintScrollbarThumb(cc::PaintCanvas* canvas,
   canvas->drawIRect(skrect, flags);
 
   SkScalar track[3];
-  SkColorToHSV(track_color_, track);
+  SkColorToHSV(kTrackColor, track);
   flags.setColor(OutlineColor(track, thumb));
   DrawBox(canvas, rect, flags);
 
@@ -941,9 +945,9 @@ SkColor NativeThemeBase::GetArrowColor(State state) const {
     return SK_ColorBLACK;
 
   SkScalar track_hsv[3];
-  SkColorToHSV(track_color_, track_hsv);
+  SkColorToHSV(kTrackColor, track_hsv);
   SkScalar thumb_hsv[3];
-  SkColorToHSV(thumb_inactive_color_, thumb_hsv);
+  SkColorToHSV(kThumbInactiveColor, thumb_hsv);
   return OutlineColor(track_hsv, thumb_hsv);
 }