initial implementation of a CSS selector matching optimization

The idea is to avoid repeated checks of CssSimpleSelector against the
same part of the doctree.
E.g

.navigation * { background-color:green }

Would result in checking for class="navigation" all the way down to the
document root for all elements.
The optimization shortcuts this, for parts of the doctree that have been
checked before.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/css.hh b/src/css.hh
index 515831e9..9acdb0e9 100644
--- a/src/css.hh
+++ b/src/css.hh
@@ -223,6 +223,7 @@ class CssSelector {
 
    private:
       struct CombinatorAndSelector {
+         int notMatchingBefore; // used for optimizing CSS selector matching
          Combinator combinator;
          CssSimpleSelector selector;
       };