Split NativeThemeAura into Overlay and NonOverlay versions.

ui/native_theme/native_theme_aura.cc

Index: ui/native_theme/native_theme_aura.cc
diff --git a/ui/native_theme/native_theme_aura.cc b/ui/native_theme/native_theme_aura.cc
index dc7166e6c491181340db32218f2f768dc48c7bab..4c0bf9e08030184ac20928ee8e5949a4be801df8 100644
--- a/ui/native_theme/native_theme_aura.cc
+++ b/ui/native_theme/native_theme_aura.cc
@@ -21,38 +21,21 @@
 #include "ui/gfx/path.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/native_theme/common_theme.h"
-#include "ui/native_theme/native_theme_switches.h"
-#include "ui/native_theme/overlay_scrollbar_constants_aura.h"
 
 namespace ui {
 
 namespace {
 
-// Constants for painting overlay scrollbars. Other properties needed outside
-// this painting code are defined in overlay_scrollbar_constants_aura.h.
-constexpr int kOverlayScrollbarStrokeWidth = 1;
-constexpr int kOverlayScrollbarMinimumLength = 12;
-constexpr SkAlpha kOverlayScrollbarAlphaNormal = 0x4D;
-constexpr SkAlpha kOverlayScrollbarAlphaHovered = 0x80;
-constexpr SkAlpha kOverlayScrollbarAlphaPressed = 0x80;
-
-// Indexed by ScrollbarOverlayColorTheme.
-constexpr SkColor kOverlayScrollbarThumbColor[] = {SK_ColorBLACK,
-                                                   SK_ColorWHITE};
-constexpr SkColor kOverlayScrollbarStrokeColor[] = {SK_ColorWHITE,
-                                                    SK_ColorBLACK};
-
 SkAlpha ThumbAlphaForState(NativeTheme::State state) {
-  bool overlay = IsOverlayScrollbarEnabled();
   switch (state) {
     case NativeTheme::kDisabled:
       return 0x00;
     case NativeTheme::kHovered:
-      return overlay ? kOverlayScrollbarAlphaHovered : 0x4D;
+      return 0x4D;
     case NativeTheme::kNormal:
-      return overlay ? kOverlayScrollbarAlphaNormal : 0x33;
+      return 0x33;
     case NativeTheme::kPressed:
-      return overlay ? kOverlayScrollbarAlphaPressed : 0x80;
+      return 0x80;
     case NativeTheme::kNumStates:
       break;
   }
@@ -66,11 +49,6 @@ const SkColor kTrackColor = SkColorSetRGB(0xF1, 0xF1, 0xF1);
 }  // namespace
 
 // static
-NativeTheme* NativeTheme::GetInstanceForWeb() {
-  return NativeThemeAura::instance();
-}
-
-// static
 NativeThemeAura* NativeThemeAura::instance() {
   CR_DEFINE_STATIC_LOCAL(NativeThemeAura, s_native_theme, ());
   return &s_native_theme;
@@ -82,11 +60,6 @@ NativeThemeAura::NativeThemeAura() {
   set_scrollbar_button_length(0);
 #endif
 
-  if (IsOverlayScrollbarEnabled()) {
-    scrollbar_width_ =
-        kOverlayScrollbarThumbWidthPressed + kOverlayScrollbarStrokeWidth * 2;
-  }
-
   // Images and alphas declarations assume the following order.
   static_assert(kDisabled == 0, "states unexpectedly changed");
   static_assert(kHovered == 1, "states unexpectedly changed");
@@ -173,8 +146,6 @@ void NativeThemeAura::PaintScrollbarTrack(
     State state,
     const ScrollbarTrackExtraParams& extra_params,
     const gfx::Rect& rect) const {
-  // Overlay Scrollbar should never paint a scrollbar track.
-  DCHECK(!IsOverlayScrollbarEnabled());
   SkPaint paint;
   paint.setColor(kTrackColor);
   canvas->drawIRect(gfx::RectToSkIRect(rect), paint);
@@ -185,7 +156,7 @@ void NativeThemeAura::PaintScrollbarThumb(
     Part part,
     State state,
     const gfx::Rect& rect,
-    ScrollbarOverlayColorTheme theme) const {
+    ScrollbarOverlayColorTheme) const {
   // Do not paint if state is disabled.
   if (state == kDisabled)
     return;
@@ -196,37 +167,17 @@ void NativeThemeAura::PaintScrollbarThumb(
   SkColor thumb_color;
   SkAlpha thumb_alpha = ThumbAlphaForState(state);
 
-  if (IsOverlayScrollbarEnabled()) {
-    thumb_color = kOverlayScrollbarThumbColor[theme];
-
-    // In overlay mode, draw a stroke (border).
-    constexpr int kStrokeWidth = kOverlayScrollbarStrokeWidth;
-    SkPaint paint;
-    paint.setColor(
-        SkColorSetA(kOverlayScrollbarStrokeColor[theme], thumb_alpha));
-    paint.setStyle(SkPaint::kStroke_Style);
-    paint.setStrokeWidth(kStrokeWidth);
-
-    gfx::RectF stroke_rect(thumb_rect);
-    constexpr float kHalfStrokeWidth = kStrokeWidth / 2.f;
-    stroke_rect.Inset(kHalfStrokeWidth, kHalfStrokeWidth);
-    canvas->drawRect(gfx::RectFToSkRect(stroke_rect), paint);
+  // If there are no scrollbuttons then provide some padding so that the thumb
+  // doesn't touch the top of the track.
+  const int kThumbPadding = 2;
+  const int extra_padding =
+      (scrollbar_button_length() == 0) ? kThumbPadding : 0;
+  if (part == NativeTheme::kScrollbarVerticalThumb)
+    thumb_rect.Inset(kThumbPadding, extra_padding);
+  else
+    thumb_rect.Inset(extra_padding, kThumbPadding);
 
-    // Inset the all the edges edges so we fill-in the stroke below.
-    thumb_rect.Inset(kStrokeWidth, kStrokeWidth);
-  } else {
-    // If there are no scrollbuttons then provide some padding so that the thumb
-    // doesn't touch the top of the track.
-    const int kThumbPadding = 2;
-    const int extra_padding =
-        (scrollbar_button_length() == 0) ? kThumbPadding : 0;
-    if (part == NativeTheme::kScrollbarVerticalThumb)
-      thumb_rect.Inset(kThumbPadding, extra_padding);
-    else
-      thumb_rect.Inset(extra_padding, kThumbPadding);
-
-    thumb_color = SK_ColorBLACK;
-  }
+  thumb_color = SK_ColorBLACK;
 
   SkPaint paint;
   paint.setColor(SkColorSetA(thumb_color, thumb_alpha));
@@ -236,38 +187,9 @@ void NativeThemeAura::PaintScrollbarThumb(
 void NativeThemeAura::PaintScrollbarCorner(SkCanvas* canvas,
                                            State state,
                                            const gfx::Rect& rect) const {
-  // Overlay Scrollbar should never paint a scrollbar corner.
-  DCHECK(!IsOverlayScrollbarEnabled());
   SkPaint paint;
   paint.setColor(SkColorSetRGB(0xDC, 0xDC, 0xDC));
   canvas->drawIRect(RectToSkIRect(rect), paint);
 }
 
-gfx::Size NativeThemeAura::GetPartSize(Part part,
-                                       State state,
-                                       const ExtraParams& extra) const {
-  if (IsOverlayScrollbarEnabled()) {
-    constexpr int minimum_length =
-        kOverlayScrollbarMinimumLength + 2 * kOverlayScrollbarStrokeWidth;
-
-    // Aura overlay scrollbars need a slight tweak from the base sizes.
-    switch (part) {
-      case kScrollbarHorizontalThumb:
-        return gfx::Size(minimum_length, scrollbar_width_);
-      case kScrollbarVerticalThumb:
-        return gfx::Size(scrollbar_width_, minimum_length);
-      default:
-        // TODO(bokan): We should probably make sure code using overlay
-        // scrollbars isn't asking for part sizes that don't exist. This
-        // currently breaks in Views layout code which indicates they aren't
-        // overlay aware yet. The Views code should be fixed and either this
-        // branch return 0 for parts that don't exist or assert NOTREACHED.
-        // crbug.com/657159.
-        break;
-    }
-  }
-
-  return NativeThemeBase::GetPartSize(part, state, extra);
-}
-
 }  // namespace ui