Bug 1619664 - Remove nsBox::gTheme. r=dholbert

The boxes can just poke at the prescontext theme like literally everything else.

Differential Revision: https://phabricator.services.mozilla.com/D65161

layout/build/nsLayoutStatics.cpp

@@ -348,7 +348,6 @@ void nsLayoutStatics::Shutdown() {
   nsCSSProps::ReleaseTable();
   nsRepeatService::Shutdown();
   nsStackLayout::Shutdown();
-  nsBox::Shutdown();
 
 #ifdef MOZ_XUL
   nsXULContentUtils::Finish();

layout/xul/nsBox.cpp

@@ -53,18 +53,9 @@ nsresult nsBox::EndXULLayout(nsBoxLayoutState& aState) {
   return SyncLayout(aState);
 }
 
-bool nsBox::gGotTheme = false;
-StaticRefPtr<nsITheme> nsBox::gTheme;
-
 nsBox::nsBox(ComputedStyle* aStyle, nsPresContext* aPresContext, ClassID aID)
     : nsIFrame(aStyle, aPresContext, aID) {
   MOZ_COUNT_CTOR(nsBox);
-  if (!gGotTheme) {
-    gTheme = do_GetNativeTheme();
-    if (gTheme) {
-      gGotTheme = true;
-    }
-  }
 }
 
 nsBox::~nsBox() {
@@ -73,12 +64,6 @@ nsBox::~nsBox() {
   MOZ_COUNT_DTOR(nsBox);
 }
 
-/* static */
-void nsBox::Shutdown() {
-  gGotTheme = false;
-  gTheme = nullptr;
-}
-
 nsresult nsBox::XULRelayoutChildAtOrdinal(nsIFrame* aChild) { return NS_OK; }
 
 nsresult nsIFrame::GetXULClientRect(nsRect& aClientRect) {
@@ -142,14 +127,15 @@ nsresult nsBox::GetXULBorder(nsMargin& aMargin) {
   aMargin.SizeTo(0, 0, 0, 0);
 
   const nsStyleDisplay* disp = StyleDisplay();
-  if (disp->HasAppearance() && gTheme) {
+  if (disp->HasAppearance()) {
     // Go to the theme for the border.
-    nsPresContext* context = PresContext();
-    if (gTheme->ThemeSupportsWidget(context, this, disp->mAppearance)) {
-      LayoutDeviceIntMargin margin = gTheme->GetWidgetBorder(
-          context->DeviceContext(), this, disp->mAppearance);
+    nsPresContext* pc = PresContext();
+    nsITheme* theme = pc->GetTheme();
+    if (theme && theme->ThemeSupportsWidget(pc, this, disp->mAppearance)) {
+      LayoutDeviceIntMargin margin =
+          theme->GetWidgetBorder(pc->DeviceContext(), this, disp->mAppearance);
       aMargin =
-          LayoutDevicePixel::ToAppUnits(margin, context->AppUnitsPerDevPixel());
+          LayoutDevicePixel::ToAppUnits(margin, pc->AppUnitsPerDevPixel());
       return NS_OK;
     }
   }
@@ -161,16 +147,17 @@ nsresult nsBox::GetXULBorder(nsMargin& aMargin) {
 
 nsresult nsBox::GetXULPadding(nsMargin& aPadding) {
   const nsStyleDisplay* disp = StyleDisplay();
-  if (disp->HasAppearance() && gTheme) {
+  if (disp->HasAppearance()) {
     // Go to the theme for the padding.
-    nsPresContext* context = PresContext();
-    if (gTheme->ThemeSupportsWidget(context, this, disp->mAppearance)) {
+    nsPresContext* pc = PresContext();
+    nsITheme* theme = pc->GetTheme();
+    if (theme && theme->ThemeSupportsWidget(pc, this, disp->mAppearance)) {
       LayoutDeviceIntMargin padding;
-      bool useThemePadding = gTheme->GetWidgetPadding(
-          context->DeviceContext(), this, disp->mAppearance, &padding);
+      bool useThemePadding = theme->GetWidgetPadding(
+          pc->DeviceContext(), this, disp->mAppearance, &padding);
       if (useThemePadding) {
-        aPadding = LayoutDevicePixel::ToAppUnits(
-            padding, context->AppUnitsPerDevPixel());
+        aPadding =
+            LayoutDevicePixel::ToAppUnits(padding, pc->AppUnitsPerDevPixel());
         return NS_OK;
       }
     }

layout/xul/nsBox.h

@@ -17,8 +17,6 @@ class nsBox : public nsIFrame {
  public:
   friend class nsIFrame;
 
-  static void Shutdown();
-
   virtual nsSize GetXULPrefSize(nsBoxLayoutState& aBoxLayoutState) override;
   virtual nsSize GetXULMinSize(nsBoxLayoutState& aBoxLayoutState) override;
   virtual nsSize GetXULMaxSize(nsBoxLayoutState& aBoxLayoutState) override;
@@ -81,9 +79,6 @@ class nsBox : public nsIFrame {
   nsresult BeginXULLayout(nsBoxLayoutState& aState);
   NS_IMETHOD DoXULLayout(nsBoxLayoutState& aBoxLayoutState);
   nsresult EndXULLayout(nsBoxLayoutState& aState);
-
-  static bool gGotTheme;
-  static mozilla::StaticRefPtr<nsITheme> gTheme;
 };
 
 #endif

layout/xul/nsImageBoxFrame.cpp

@@ -606,10 +606,13 @@ bool nsImageBoxFrame::CanOptimizeToImageLayer() {
 
 imgRequestProxy* nsImageBoxFrame::GetRequestFromStyle() {
   const nsStyleDisplay* disp = StyleDisplay();
-  if (disp->HasAppearance() && nsBox::gTheme &&
-      nsBox::gTheme->ThemeSupportsWidget(nullptr, this, disp->mAppearance)) {
+  if (disp->HasAppearance()) {
+    nsPresContext* pc = PresContext();
+    nsITheme* theme = pc->GetTheme();
+    if (theme && theme->ThemeSupportsWidget(pc, this, disp->mAppearance)) {
       return nullptr;
     }
+  }
 
   return StyleList()->GetListStyleImage();
 }