Fix WHITESPACE issues in the CSS grammar.

LayoutTests/css3/filters/custom-with-at-rule-syntax/parsing-at-rule-valid-expected.txt

Index: LayoutTests/css3/filters/custom-with-at-rule-syntax/parsing-at-rule-valid-expected.txt
diff --git a/LayoutTests/css3/filters/custom-with-at-rule-syntax/parsing-at-rule-valid-expected.txt b/LayoutTests/css3/filters/custom-with-at-rule-syntax/parsing-at-rule-valid-expected.txt
index 338fb6ad49b3a9605e3f3cbaf57ed8597d621701..4cd9442ff8e8e42df3d910a16c47a0242b3bff30 100644
--- a/LayoutTests/css3/filters/custom-with-at-rule-syntax/parsing-at-rule-valid-expected.txt
+++ b/LayoutTests/css3/filters/custom-with-at-rule-syntax/parsing-at-rule-valid-expected.txt
@@ -55,6 +55,42 @@ PASS cssRule.constructor === WebKitCSSFilterRule is true
 PASS cssRule.__proto__ === WebKitCSSFilterRule.prototype is true
 PASS declaration.length is 0
 
+Empty rule, comment separators
+@-webkit-filter/**/my-filter/**/{ }
+PASS cssRule.cssText is "@-webkit-filter my-filter { }"
+PASS cssRule.type is CSSRule.WEBKIT_FILTER_RULE
+PASS cssRule instanceof WebKitCSSFilterRule is true
+PASS cssRule.constructor === WebKitCSSFilterRule is true
+PASS cssRule.__proto__ === WebKitCSSFilterRule.prototype is true
+PASS declaration.length is 0
+
+Empty rule, comment+space separators
+@-webkit-filter/**/ my-filter/**/ { }
+PASS cssRule.cssText is "@-webkit-filter my-filter { }"
+PASS cssRule.type is CSSRule.WEBKIT_FILTER_RULE
+PASS cssRule instanceof WebKitCSSFilterRule is true
+PASS cssRule.constructor === WebKitCSSFilterRule is true
+PASS cssRule.__proto__ === WebKitCSSFilterRule.prototype is true
+PASS declaration.length is 0
+
+Empty rule, space+comment separators
+@-webkit-filter /**/my-filter /**/{ }
+PASS cssRule.cssText is "@-webkit-filter my-filter { }"
+PASS cssRule.type is CSSRule.WEBKIT_FILTER_RULE
+PASS cssRule instanceof WebKitCSSFilterRule is true
+PASS cssRule.constructor === WebKitCSSFilterRule is true
+PASS cssRule.__proto__ === WebKitCSSFilterRule.prototype is true
+PASS declaration.length is 0
+
+Empty rule, space+comment+space separators
+@-webkit-filter /**/ my-filter /**/ { }
+PASS cssRule.cssText is "@-webkit-filter my-filter { }"
+PASS cssRule.type is CSSRule.WEBKIT_FILTER_RULE
+PASS cssRule instanceof WebKitCSSFilterRule is true
+PASS cssRule.constructor === WebKitCSSFilterRule is true
+PASS cssRule.__proto__ === WebKitCSSFilterRule.prototype is true
+PASS declaration.length is 0
+
 ========================================
 Nested filter at-rule tests.
 ========================================