Fix scrollbar buttons at hidpi when enable-use-zoom-for-dsf is on.

content/child/webthemeengine_impl_default.cc

Index: content/child/webthemeengine_impl_default.cc
diff --git a/content/child/webthemeengine_impl_default.cc b/content/child/webthemeengine_impl_default.cc
index 37373fd9dfc87586d4ba3d57c7eb0170597ed33b..3cbc96027f92082ba66c7953330e541f095c5884 100644
--- a/content/child/webthemeengine_impl_default.cc
+++ b/content/child/webthemeengine_impl_default.cc
@@ -16,24 +16,6 @@ using blink::WebRect;
 using blink::WebThemeEngine;
 
 namespace content {
-namespace {
-
-#if defined(OS_WIN)
-// The scrollbar metrics default to 17 dips which is the default value on
-// Windows in most cases.
-int32_t g_vertical_scroll_bar_width = 17;

[esprehn, 2016/04/25 23:12:11]

what sets these values now?

[Bret, 2016/04/25 23:24:32]

Nothing, they were only used in the vestigial pre-hidpi case that I fixed in
ScrollbarThemeAura.

-
-// The height of a horizontal scroll bar in dips.
-int32_t g_horizontal_scroll_bar_height = 17;
-
-// The height of the arrow bitmap on a vertical scroll bar in dips.
-int32_t g_vertical_arrow_bitmap_height = 17;
-
-// The width of the arrow bitmap on a horizontal scroll bar in dips.
-int32_t g_horizontal_arrow_bitmap_width = 17;
-#endif
-
-}  // namespace
 
 static ui::NativeTheme::Part NativeThemePart(
     WebThemeEngine::Part part) {
@@ -185,27 +167,8 @@ static void GetNativeThemeExtraParams(
 
 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) {
-    case ui::NativeTheme::kScrollbarDownArrow:
-    case ui::NativeTheme::kScrollbarLeftArrow:
-    case ui::NativeTheme::kScrollbarRightArrow:
-    case ui::NativeTheme::kScrollbarUpArrow:
-    case ui::NativeTheme::kScrollbarHorizontalThumb:
-    case ui::NativeTheme::kScrollbarVerticalThumb:
-    case ui::NativeTheme::kScrollbarHorizontalTrack:
-    case ui::NativeTheme::kScrollbarVerticalTrack: {
-      return gfx::Size(g_vertical_scroll_bar_width,
-                       g_vertical_scroll_bar_width);
-    }
-
-    default:
-      break;
-  }
-#endif
   return ui::NativeTheme::GetInstanceForWeb()->GetPartSize(
-      native_theme_part, ui::NativeTheme::kNormal, extra);
+      NativeThemePart(part), ui::NativeTheme::kNormal, extra);
 }
 
 void WebThemeEngineImpl::paint(
@@ -233,18 +196,4 @@ void WebThemeEngineImpl::paintStateTransition(blink::WebCanvas* canvas,
       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