Reviewers: skybrian, tbroyer, Description: Add new CSS FunctionValue type as a first-class representation of value functions, hook it up into the @def replacer.
This means that gradients can now take @def constants. This also fixes issues with function arguments losing spaces - no more literal() hacks needed. Fixes issue: 5771 Please review this at http://gwt-code-reviews.appspot.com/1735804/ Affected files: M user/src/com/google/gwt/resources/css/GenerateCssAst.java M user/src/com/google/gwt/resources/css/SubstitutionReplacer.java M user/src/com/google/gwt/resources/css/ast/CssProperty.java M user/test/com/google/gwt/resources/client/CSSResourceTest.java M user/test/com/google/gwt/resources/client/test.css -- http://groups.google.com/group/Google-Web-Toolkit-Contributors
