DevTools: Split creating inspector stylesheet and adding a new rule into stylesheet in protocol.

LayoutTests/inspector-protocol/css/css-protocol-test.js

+function initialize_cssTest()
+{
+
+InspectorTest.dumpRuleMatch = function(ruleMatch)
+{
+    function log(indent, string)
+    {
+        var indentString = Array(indent+1).join(" ");
+        InspectorTest.log(indentString + string);
+    }
+
+    var rule = ruleMatch.rule;
+    var matchingSelectors = ruleMatch.matchingSelectors;
+    var selectorLine = "";
+    var selectors = rule.selectorList.selectors;
+    for (var i = 0; i < selectors.length; ++i) {
+        if (i > 0)
+            selectorLine += ", ";
+        var matching = matchingSelectors.indexOf(i) !== -1;
+        if (matching)
+            selectorLine += "*";
+        selectorLine += selectors[i].value;
+        if (matching)
+            selectorLine += "*";
+    }
+    selectorLine += " {";
+    selectorLine += "    " + rule.origin + (rule.sourceURL ? " (" + InspectorTest.displayName(rule.sourceURL) + ")" : "");
+    log(0, selectorLine);
+    var style = rule.style;
+    var cssProperties = style.cssProperties;
+    for (var i = 0; i < cssProperties.length; ++i) {
+        var cssProperty = cssProperties[i];
+        var propertyLine = cssProperty.name + ": " + cssProperty.value + ";";
+        log(4, propertyLine);
+    }
+    log(0, "}");
+};
+
+InspectorTest.displayName = function(url)
+{
+    return url.substr(url.lastIndexOf("/") + 1);
+};
+
+InspectorTest.loadAndDumpMatchingRules = function(nodeId, callback)
+{
+    InspectorTest.requestNodeId(nodeId, nodeIdLoaded);
+
+    function nodeIdLoaded(nodeId)
+    {
+        InspectorTest.sendCommandOrDie("CSS.getMatchedStylesForNode", { "nodeId": nodeId }, matchingRulesLoaded);
+    }
+
+    function matchingRulesLoaded(result)
+    {
+        InspectorTest.log("Dumping matched rules: ");
+        var ruleMatches = result.matchedCSSRules;
+        for (var i = 0; i < ruleMatches.length; ++i) {
+            var ruleMatch = ruleMatches[i];
+            var origin = ruleMatch.rule.origin;
+            if (origin !== "inspector" && origin !== "regular")
+                continue;
+            InspectorTest.dumpRuleMatch(ruleMatch);
+        }
+        callback();
+    }
+}
+
+}