DevTools: [SSP] Implement adding new rule in user stylesheet

LayoutTests/inspector-protocol/css/css-create-stylesheet-and-add-rule.html

Index: LayoutTests/inspector-protocol/css/css-create-stylesheet-and-add-rule.html
diff --git a/LayoutTests/inspector-protocol/css/css-create-stylesheet-and-add-rule.html b/LayoutTests/inspector-protocol/css/css-create-stylesheet-and-add-rule.html
index 60235ea2c76d02b82596cc2dacbec04633aa6759..2bde18db52859cd1587abad84539861119ea1794 100644
--- a/LayoutTests/inspector-protocol/css/css-create-stylesheet-and-add-rule.html
+++ b/LayoutTests/inspector-protocol/css/css-create-stylesheet-and-add-rule.html
@@ -40,7 +40,10 @@ function test()
     function step3()
     {
         InspectorTest.log("Adding a rule to the existing stylesheet.");
-        InspectorTest.sendCommandOrDie("CSS.addRule", { styleSheetId: styleSheetHeader.styleSheetId, selector: "#inspected" }, step4);
+        InspectorTest.addRule(styleSheetHeader.styleSheetId, false, {
+            location: { startLine: 0, startColumn: 0, endLine: 0, endColumn: 0 },
+            ruleText: "#inspected {}",
+        }, step4);
     }
 
     function step4()
@@ -57,7 +60,10 @@ function test()
     function step6(result)
     {
         InspectorTest.log("Adding a rule to the inspector stylesheet.");
-        InspectorTest.sendCommandOrDie("CSS.addRule", { styleSheetId: result.styleSheetId, selector: "#inspected" }, step7);
+        InspectorTest.addRule(result.styleSheetId, false, {
+            location: { startLine: 0, startColumn: 0, endLine: 0, endColumn: 0 },
+            ruleText: "#inspected {}",
+        }, step7);
     }
 
     function step7()