core: layout: omit bottom row when explicitly disabled by main layout

The main layout (e.g. latn_bone.xml and latn_neo2.xml) may disable the
bottom row by adding a property to the XML keyboard tag. Omit the bottom
row when this is the case.

src/core/layout.rs

@@ -519,6 +519,7 @@ const KEYSYMS: [(&str, Keysym, &str); 21] = [
 
 struct LayoutFile {
     rows: Vec<Vec<Key>>,
+    has_bottom_row: bool,
     width: f64,
     height: f64,
     row_width: f64,
@@ -581,12 +582,21 @@ impl LayoutFile {
         self.row_width = 0.0;
     }
 
+    fn start_keyboard(&mut self, attrs: &HashMap<&str, &str>)
+    {
+        if *attrs.get("bottom_row").unwrap_or(&"") == "false" {
+            self.has_bottom_row = false;
+        }
+    }
+
     fn start_elem(&mut self, name: &str, attrs: &HashMap<&str, &str>)
     {
         if name == "key" {
             self.start_key(attrs);
         } else if name == "row" {
             self.start_row();
+        } else if name == "keyboard" {
+            self.start_keyboard(attrs);
         }
     }
 
@@ -612,6 +622,7 @@ impl LayoutFile {
     {
         let mut layout = LayoutFile {
             rows: Vec::new(),
+            has_bottom_row: true,
             width: 0.0,
             height: 0.0,
             row_width: 0.0,
@@ -707,6 +718,7 @@ impl Layout {
             text_supp: false,
         };
 
+        if main_layout.has_bottom_row {
             let path = dir.join("bottom_row.xml");
             let bottom_row = LayoutFile::load(path)?;
 
@@ -729,6 +741,7 @@ impl Layout {
 
                 layout.rows.push(new_row);
             }
+        }
 
         Ok(layout)
     }