Aura overlay scrollbars adjust color for dark backgrounds

content/child/webthemeengine_impl_default.cc

 // Copyright 2014 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 "content/child/webthemeengine_impl_default.h"
 
 #include "build/build_config.h"
 #include "skia/ext/platform_canvas.h"
 #include "third_party/WebKit/public/platform/WebRect.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
 #include "ui/native_theme/native_theme.h"
 
 using blink::WebCanvas;
 using blink::WebColor;
 using blink::WebRect;
 using blink::WebThemeEngine;
+using blink::WebScrollbarOverlayColorTheme;
 
 namespace content {
 namespace {
 
 #if defined(OS_WIN)
 // The width of a vertical scroll bar in dips.
 int32_t g_vertical_scroll_bar_width;
 
 // The height of a horizontal scroll bar in dips.
 int32_t g_horizontal_scroll_bar_height;
@@ skipping 44 matching lines @@
       return ui::NativeTheme::kSliderThumb;
     case WebThemeEngine::PartInnerSpinButton:
       return ui::NativeTheme::kInnerSpinButton;
     case WebThemeEngine::PartProgressBar:
       return ui::NativeTheme::kProgressBar;
     default:
       return ui::NativeTheme::kScrollbarDownArrow;
   }
 }
 
+static ui::NativeTheme::ScrollbarOverlayColorTheme
+NativeThemeScrollbarOverlayColorTheme(WebScrollbarOverlayColorTheme theme) {
+  switch (theme) {
+    case WebScrollbarOverlayColorTheme::WebScrollbarOverlayColorThemeLight:
+      return ui::NativeTheme::ScrollbarOverlayColorThemeLight;
+    case WebScrollbarOverlayColorTheme::WebScrollbarOverlayColorThemeDark:
+      return ui::NativeTheme::ScrollbarOverlayColorThemeDark;
+    default:
+      return ui::NativeTheme::ScrollbarOverlayColorThemeDark;
+  }
+}
+
 static ui::NativeTheme::State NativeThemeState(
     WebThemeEngine::State state) {
   switch (state) {
     case WebThemeEngine::StateDisabled:
       return ui::NativeTheme::kDisabled;
     case WebThemeEngine::StateHover:
       return ui::NativeTheme::kHovered;
     case WebThemeEngine::StateNormal:
       return ui::NativeTheme::kNormal;
     case WebThemeEngine::StatePressed:
       return ui::NativeTheme::kPressed;
     default:
       return ui::NativeTheme::kDisabled;
   }
 }
 
 static void GetNativeThemeExtraParams(
     WebThemeEngine::Part part,
     WebThemeEngine::State state,
     const WebThemeEngine::ExtraParams* extra_params,
     ui::NativeTheme::ExtraParams* native_theme_extra_params) {
+  if (!extra_params)
+    return;
+
   switch (part) {
     case WebThemeEngine::PartScrollbarHorizontalTrack:
     case WebThemeEngine::PartScrollbarVerticalTrack:
       native_theme_extra_params->scrollbar_track.track_x =
           extra_params->scrollbarTrack.trackX;
       native_theme_extra_params->scrollbar_track.track_y =
           extra_params->scrollbarTrack.trackY;
       native_theme_extra_params->scrollbar_track.track_width =
           extra_params->scrollbarTrack.trackWidth;
       native_theme_extra_params->scrollbar_track.track_height =
@@ skipping 58 matching lines @@
           extra_params->progressBar.determinate;
       native_theme_extra_params->progress_bar.value_rect_x =
           extra_params->progressBar.valueRectX;
       native_theme_extra_params->progress_bar.value_rect_y =
           extra_params->progressBar.valueRectY;
       native_theme_extra_params->progress_bar.value_rect_width =
           extra_params->progressBar.valueRectWidth;
       native_theme_extra_params->progress_bar.value_rect_height =
           extra_params->progressBar.valueRectHeight;
       break;
+    case WebThemeEngine::PartScrollbarHorizontalThumb:
+    case WebThemeEngine::PartScrollbarVerticalThumb:
+      native_theme_extra_params->scrollbar_thumb.scrollbar_theme =
+          NativeThemeScrollbarOverlayColorTheme(
+              extra_params->scrollbarThumb.scrollbarTheme);
+      break;
     default:
       break;  // Parts that have no extra params get here.
   }
 }
 
 blink::WebSize WebThemeEngineImpl::getSize(WebThemeEngine::Part part) {
   ui::NativeTheme::ExtraParams extra;
   ui::NativeTheme::Part native_theme_part = NativeThemePart(part);
 #if defined(OS_WIN)
   switch (native_theme_part) {
@@ skipping 24 matching lines @@
     const blink::WebRect& rect,
     const WebThemeEngine::ExtraParams* extra_params) {
   ui::NativeTheme::ExtraParams native_theme_extra_params;
   GetNativeThemeExtraParams(
       part, state, extra_params, &native_theme_extra_params);
   ui::NativeTheme::GetInstanceForWeb()->Paint(
       canvas, NativeThemePart(part), NativeThemeState(state), gfx::Rect(rect),
       native_theme_extra_params);
 }
 
-void WebThemeEngineImpl::paintStateTransition(blink::WebCanvas* canvas,
-                                              WebThemeEngine::Part part,
-                                              WebThemeEngine::State startState,
-                                              WebThemeEngine::State endState,
-                                              double progress,
-                                              const blink::WebRect& rect) {
-  ui::NativeTheme::GetInstanceForWeb()->PaintStateTransition(
-      canvas, NativeThemePart(part), NativeThemeState(startState),
-      NativeThemeState(endState), progress, gfx::Rect(rect));
-}
-
 #if defined(OS_WIN)
 // static
 void WebThemeEngineImpl::cacheScrollBarMetrics(
     int32_t vertical_scroll_bar_width,
     int32_t horizontal_scroll_bar_height,
     int32_t vertical_arrow_bitmap_height,
     int32_t horizontal_arrow_bitmap_width) {
   g_vertical_scroll_bar_width = vertical_scroll_bar_width;
   g_horizontal_scroll_bar_height = horizontal_scroll_bar_height;
   g_vertical_arrow_bitmap_height = vertical_arrow_bitmap_height;
   g_horizontal_arrow_bitmap_width = horizontal_arrow_bitmap_width;
 }
 #endif
 
 }  // namespace content