LibPDF: Resize fonts when the text and line matrices change

Author: https://github.com/mattco98
Commit: 5f8fd47214
Pull-request: https://github.com/SerenityOS/serenity/pull/20084
Reviewed-by: https://github.com/nico ✅

Userland/Libraries/LibPDF/Renderer.cpp

@@ -458,6 +458,13 @@ RENDERER_HANDLER(text_set_matrix_and_line_matrix)
     m_text_line_matrix = new_transform;
     m_text_matrix = new_transform;
     m_text_rendering_matrix_is_dirty = true;
+
+    // Settings the text/line matrix retroactively affects fonts
+    if (text_state().font) {
+        auto new_text_rendering_matrix = calculate_text_rendering_matrix();
+        text_state().font->set_font_size(text_state().font_size * new_text_rendering_matrix.x_scale());
+    }
+
     return {};
 }