new EliminateUselessRulesetNodes(cssTree).runPass();
// Merge of rules with same selector.
new MergeAdjacentRulesetNodesWithSameSelector(cssTree).runPass();
new EliminateUselessRulesetNodes(cssTree).runPass();
// Merge of rules with same styles.
new MergeAdjacentRulesetNodesWithSameDeclarations(cssTree).runPass();
new EliminateUselessRulesetNodes(cssTree).runPass();
}
return collectConstantDefinitionsPass.getConstantDefinitions();
}