DevTools: [CSS] Add CSS.editRangeInStyleSheetText() to the protocol

LayoutTests/inspector-protocol/css/css-get-platform-fonts.html

Index: LayoutTests/inspector-protocol/css/css-get-platform-fonts.html
diff --git a/LayoutTests/inspector-protocol/css/css-get-platform-fonts.html b/LayoutTests/inspector-protocol/css/css-get-platform-fonts.html
index eed1432e2d50cd9cf28630087cecb5bcf9cd9b76..2d919d981d4d994332341b590e7edef2fdaff39b 100644
--- a/LayoutTests/inspector-protocol/css/css-get-platform-fonts.html
+++ b/LayoutTests/inspector-protocol/css/css-get-platform-fonts.html
@@ -5,29 +5,17 @@
 
 function test()
 {
-    function sendCommand(command, properties, callback) {
-        InspectorTest.sendCommand(command, properties || {}, commandCallback);
-        function commandCallback(msg)
-        {
-            if (msg.error) {
-                InspectorTest.log(msg.error.message);
-                InspectorTest.completeTest();
-                return;
-            }
-            callback(msg.result);
-        }
-    }
-    sendCommand("DOM.getDocument", {}, onGotDocument);
+    InspectorTest.sendCommandAndBailOnError("DOM.getDocument", {}, onGotDocument);
 
     function onGotDocument(result)
     {
         var root = result.root;
-        sendCommand("DOM.querySelector", { "nodeId": root.nodeId , "selector": "#fancy" }, onGotNode);
+        InspectorTest.sendCommandAndBailOnError("DOM.querySelector", { "nodeId": root.nodeId , "selector": "#fancy" }, onGotNode);
     }
 
     function onGotNode(node)
     {
-        sendCommand("CSS.getPlatformFontsForNode", { "nodeId": node.nodeId }, onGotComputedFonts);
+        InspectorTest.sendCommandAndBailOnError("CSS.getPlatformFontsForNode", { "nodeId": node.nodeId }, onGotComputedFonts);
     }
 
     function onGotComputedFonts(response)