LibWeb: Let FormattingContext decide the automatic width of its root

Instead of special-casing FlexFormattingContext in the intrinsic sizing
layout helpers, add FormattingContext::automatic_content_width() and let
each context subclass decide what that means.

No behavior change here, just moving this responsibility.

Userland/Libraries/LibWeb/Layout/BlockFormattingContext.cpp

@@ -38,6 +38,11 @@ BlockFormattingContext::~BlockFormattingContext()
     }
 }
 
+CSSPixels BlockFormattingContext::automatic_content_width() const
+{
+    return greatest_child_width(root());
+}
+
 CSSPixels BlockFormattingContext::automatic_content_height() const
 {
     return compute_auto_height_for_block_formatting_context_root(root());
@@ -925,7 +930,7 @@ BlockFormattingContext::SpaceUsedByFloats BlockFormattingContext::space_used_by_
     return space_used_by_floats;
 }
 
-CSSPixels BlockFormattingContext::greatest_child_width(Box const& box)
+CSSPixels BlockFormattingContext::greatest_child_width(Box const& box) const
 {
     // Similar to FormattingContext::greatest_child_width()
     // but this one takes floats into account!

Userland/Libraries/LibWeb/Layout/BlockFormattingContext.h

@@ -22,6 +22,7 @@ public:
     ~BlockFormattingContext();
 
     virtual void run(Box const&, LayoutMode, AvailableSpace const&) override;
+    virtual CSSPixels automatic_content_width() const override;
     virtual CSSPixels automatic_content_height() const override;
 
     auto const& left_side_floats() const { return m_left_floats; }
@@ -40,7 +41,7 @@ public:
 
     SpaceUsedByFloats space_used_by_floats(CSSPixels y) const;
 
-    virtual CSSPixels greatest_child_width(Box const&) override;
+    virtual CSSPixels greatest_child_width(Box const&) const override;
 
     void layout_floating_box(Box const& child, BlockContainer const& containing_block, LayoutMode, AvailableSpace const&, CSSPixels y, LineBuilder* = nullptr);
 

Userland/Libraries/LibWeb/Layout/FlexFormattingContext.cpp

@@ -75,9 +75,14 @@ FlexFormattingContext::FlexFormattingContext(LayoutState& state, Box const& flex
 
 FlexFormattingContext::~FlexFormattingContext() = default;
 
+CSSPixels FlexFormattingContext::automatic_content_width() const
+{
+    return m_flex_container_state.content_width();
+}
+
 CSSPixels FlexFormattingContext::automatic_content_height() const
 {
-    return m_state.get(flex_container()).content_height();
+    return m_flex_container_state.content_height();
 }
 
 void FlexFormattingContext::run(Box const& run_box, LayoutMode, AvailableSpace const& available_content_space)

Userland/Libraries/LibWeb/Layout/FlexFormattingContext.h

@@ -19,6 +19,7 @@ public:
     virtual bool inhibits_floating() const override { return true; }
 
     virtual void run(Box const&, LayoutMode, AvailableSpace const&) override;
+    virtual CSSPixels automatic_content_width() const override;
     virtual CSSPixels automatic_content_height() const override;
 
     Box const& flex_container() const { return context_box(); }

Userland/Libraries/LibWeb/Layout/FormattingContext.cpp

@@ -127,7 +127,8 @@ OwnPtr<FormattingContext> FormattingContext::create_independent_formatting_conte
                 : FormattingContext(Type::Block, state, box)
             {
             }
-            virtual CSSPixels automatic_content_height() const override { return 0; };
+            virtual CSSPixels automatic_content_width() const override { return 0; }
+            virtual CSSPixels automatic_content_height() const override { return 0; }
             virtual void run(Box const&, LayoutMode, AvailableSpace const&) override { }
         };
         return make<ReplacedFormattingContext>(state, child_box);
@@ -170,7 +171,8 @@ OwnPtr<FormattingContext> FormattingContext::create_independent_formatting_conte
                 : FormattingContext(Type::Block, state, box)
             {
             }
-            virtual CSSPixels automatic_content_height() const override { return 0; };
+            virtual CSSPixels automatic_content_width() const override { return 0; }
+            virtual CSSPixels automatic_content_height() const override { return 0; }
             virtual void run(Box const&, LayoutMode, AvailableSpace const&) override { }
         };
         return make<DummyFormattingContext>(state, child_box);
@@ -208,7 +210,7 @@ OwnPtr<FormattingContext> FormattingContext::layout_inside(Box const& child_box,
     return independent_formatting_context;
 }
 
-CSSPixels FormattingContext::greatest_child_width(Box const& box)
+CSSPixels FormattingContext::greatest_child_width(Box const& box) const
 {
     CSSPixels max_width = 0;
     if (box.children_are_inline()) {
@@ -1093,11 +1095,7 @@ CSSPixels FormattingContext::calculate_min_content_width(Layout::Box const& box)
     auto available_height = AvailableSize::make_indefinite();
     context->run(box, LayoutMode::IntrinsicSizing, AvailableSpace(available_width, available_height));
 
-    if (context->type() == FormattingContext::Type::Flex) {
+    cache.min_content_width = context->automatic_content_width();
-        cache.min_content_width = box_state.content_width();
-    } else {
-        cache.min_content_width = context->greatest_child_width(box).value();
-    }
 
     if (!isfinite(cache.min_content_width->value())) {
         // HACK: If layout calculates a non-finite result, something went wrong. Force it to zero and log a little whine.
@@ -1131,11 +1129,7 @@ CSSPixels FormattingContext::calculate_max_content_width(Layout::Box const& box)
     auto available_height = AvailableSize::make_indefinite();
     context->run(box, LayoutMode::IntrinsicSizing, AvailableSpace(available_width, available_height));
 
-    if (context->type() == FormattingContext::Type::Flex) {
+    cache.max_content_width = context->automatic_content_width();
-        cache.max_content_width = box_state.content_width();
-    } else {
-        cache.max_content_width = context->greatest_child_width(box).value();
-    }
 
     if (!isfinite(cache.max_content_width->value())) {
         // HACK: If layout calculates a non-finite result, something went wrong. Force it to zero and log a little whine.

Userland/Libraries/LibWeb/Layout/FormattingContext.h

@@ -29,7 +29,7 @@ public:
     virtual void run(Box const&, LayoutMode, AvailableSpace const&) = 0;
 
     // This function returns the automatic content height of the context's root box.
-    virtual CSSPixels automatic_content_width() const { return 0; }
+    virtual CSSPixels automatic_content_width() const = 0;
 
     // This function returns the automatic content height of the context's root box.
     virtual CSSPixels automatic_content_height() const = 0;
@@ -64,7 +64,7 @@ public:
     CSS::Length calculate_inner_width(Layout::Box const&, AvailableSize const&, CSS::Size const& width) const;
     CSS::Length calculate_inner_height(Layout::Box const&, AvailableSize const&, CSS::Size const& height) const;
 
-    virtual CSSPixels greatest_child_width(Box const&);
+    virtual CSSPixels greatest_child_width(Box const&) const;
 
     CSSPixels containing_block_width_for(Box const& box) const { return containing_block_width_for(box, m_state); }
     CSSPixels containing_block_height_for(Box const& box) const { return containing_block_height_for(box, m_state); }

Userland/Libraries/LibWeb/Layout/GridFormattingContext.cpp

@@ -1901,6 +1901,11 @@ void GridFormattingContext::run(Box const& box, LayoutMode, AvailableSpace const
     m_automatic_content_height = total_y;
 }
 
+CSSPixels GridFormattingContext::automatic_content_width() const
+{
+    return greatest_child_width(context_box());
+}
+
 CSSPixels GridFormattingContext::automatic_content_height() const
 {
     return m_automatic_content_height;

Userland/Libraries/LibWeb/Layout/GridFormattingContext.h

@@ -62,6 +62,7 @@ public:
     ~GridFormattingContext();
 
     virtual void run(Box const&, LayoutMode, AvailableSpace const& available_space) override;
+    virtual CSSPixels automatic_content_width() const override;
     virtual CSSPixels automatic_content_height() const override;
 
 private:

Userland/Libraries/LibWeb/Layout/SVGFormattingContext.cpp

@@ -21,6 +21,11 @@ SVGFormattingContext::SVGFormattingContext(LayoutState& state, Box const& box, F
 
 SVGFormattingContext::~SVGFormattingContext() = default;
 
+CSSPixels SVGFormattingContext::automatic_content_width() const
+{
+    return 0;
+}
+
 CSSPixels SVGFormattingContext::automatic_content_height() const
 {
     return 0;

Userland/Libraries/LibWeb/Layout/SVGFormattingContext.h

@@ -17,6 +17,7 @@ public:
     ~SVGFormattingContext();
 
     virtual void run(Box const&, LayoutMode, AvailableSpace const&) override;
+    virtual CSSPixels automatic_content_width() const override;
     virtual CSSPixels automatic_content_height() const override;
 };
 

Userland/Libraries/LibWeb/Layout/TableFormattingContext.cpp

@@ -542,6 +542,11 @@ void TableFormattingContext::run(Box const& box, LayoutMode layout_mode, Availab
     m_automatic_content_height = total_content_height;
 }
 
+CSSPixels TableFormattingContext::automatic_content_width() const
+{
+    return greatest_child_width(context_box());
+}
+
 CSSPixels TableFormattingContext::automatic_content_height() const
 {
     return m_automatic_content_height;

Userland/Libraries/LibWeb/Layout/TableFormattingContext.h

@@ -19,6 +19,7 @@ public:
     ~TableFormattingContext();
 
     virtual void run(Box const&, LayoutMode, AvailableSpace const&) override;
+    virtual CSSPixels automatic_content_width() const override;
     virtual CSSPixels automatic_content_height() const override;
 
     TableBox const& table_box() const { return static_cast<TableBox const&>(context_box()); }