LibWeb: Table box width should be relative to wrapper containing block

Author: https://github.com/kalenikaliaksandr
Commit: 80578ead45
Pull-request: https://github.com/SerenityOS/serenity/pull/17011

Userland/Libraries/LibWeb/Layout/TableFormattingContext.cpp

@@ -210,7 +210,9 @@ void TableFormattingContext::compute_table_width()
 
     auto& computed_values = table_box().computed_values();
 
-    CSSPixels width_of_table_containing_block = m_state.get(*table_box().containing_block()).content_width();
+    // Percentages on 'width' and 'height' on the table are relative to the table wrapper box's containing block,
+    // not the table wrapper box itself.
+    CSSPixels width_of_table_containing_block = m_state.get(*table_wrapper().containing_block()).content_width();
 
     // The row/column-grid width minimum (GRIDMIN) width is the sum of the min-content width
     // of all the columns plus cell spacing or borders.

Userland/Libraries/LibWeb/Layout/TableFormattingContext.h

@@ -8,6 +8,7 @@
 
 #include <AK/Forward.h>
 #include <LibWeb/Layout/FormattingContext.h>
+#include <LibWeb/Layout/TableWrapper.h>
 
 namespace Web::Layout {
 
@@ -20,6 +21,10 @@ public:
     virtual CSSPixels automatic_content_height() const override;
 
     TableBox const& table_box() const { return static_cast<TableBox const&>(context_box()); }
+    TableWrapper const& table_wrapper() const
+    {
+        return verify_cast<TableWrapper>(*table_box().containing_block());
+    }
 
 private:
     void calculate_row_column_grid(Box const&);