LibWeb: Support CSS vertical-align values "top" and "bottom"

Base/res/html/misc/vertical-align.html

@@ -0,0 +1,20 @@
+<style>
+div {
+    display: inline-block;
+    border: 3px solid black;
+    padding: 5px;
+    line-height: 3;
+}
+</style>
+Hello friends: <div style="vertical-align: baseline">baseline</div>
+<br>
+Hello friends: <div style="vertical-align: top">top</div>
+<br>
+Hello friends: <div style="vertical-align: middle">middle (TODO)</div>
+<br>
+Hello friends: <div style="vertical-align: bottom">bottom</div>
+<br>
+Hello friends: <div style="vertical-align: sub">sub (TODO)</div>
+<br>
+Hello friends: <div style="vertical-align: text-top">text-top (TODO)</div>
+<br>

Base/res/html/misc/welcome.html

@@ -103,6 +103,7 @@
             <li><a href="hover.html">:hover</a></li>
             <li><a href="focus.html">:focus</a></li>
             <li><h3>Properties</h3></li>
+            <li><a href="vertical-align.html">vertical-align</a></li>
             <li><a href="backgrounds.html">Backgrounds</a></li>
             <li><a href="background-repeat-test.html">Background-repeat</a></li>
             <li><a href="box-shadow.html">Box-shadow</a></li>

Userland/Libraries/LibWeb/Layout/LineBuilder.cpp

@@ -97,6 +97,19 @@ bool LineBuilder::should_break(LayoutMode layout_mode, float next_item_width, bo
 static float box_baseline(FormattingState const& state, Box const& box)
 {
     auto const& box_state = state.get(box);
+
+    auto const& vertical_align = box.computed_values().vertical_align();
+    if (vertical_align.has<CSS::VerticalAlign>()) {
+        switch (vertical_align.get<CSS::VerticalAlign>()) {
+        case CSS::VerticalAlign::Top:
+            return box_state.border_box_top();
+        case CSS::VerticalAlign::Bottom:
+            return box_state.content_height + box_state.border_box_bottom();
+        default:
+            break;
+        }
+    }
+
     if (!box_state.line_boxes.is_empty())
         return box_state.border_box_top() + box_state.offset.y() + box_state.line_boxes.last().baseline();
     if (box.has_children() && !box.children_are_inline()) {
@@ -178,13 +191,15 @@ void LineBuilder::update_last_line()
         auto y_value_for_alignment = [&](CSS::VerticalAlign vertical_align) {
             switch (vertical_align) {
             case CSS::VerticalAlign::Baseline:
-            case CSS::VerticalAlign::Bottom:
+                return m_current_y + line_box_baseline - fragment_baseline(fragment) + fragment.border_box_top();
+            case CSS::VerticalAlign::Top:
+                return m_current_y + fragment.border_box_top();
             case CSS::VerticalAlign::Middle:
+            case CSS::VerticalAlign::Bottom:
             case CSS::VerticalAlign::Sub:
             case CSS::VerticalAlign::Super:
             case CSS::VerticalAlign::TextBottom:
             case CSS::VerticalAlign::TextTop:
-            case CSS::VerticalAlign::Top:
                 // FIXME: These are all 'baseline'
                 return m_current_y + line_box_baseline - fragment_baseline(fragment) + fragment.border_box_top();
             }