DevTools: Support asynchronous loading of resources without cross origin checks through backend for…

Source/devtools/protocol.json

 {
     "version": { "major": "1", "minor": "0" },
     "domains": [{
         "domain": "Inspector",
         "hidden": true,
         "types": [],
         "commands": [
             {
                 "name": "enable",
                 "description": "Enables inspector domain notifications."
@@ skipping 1026 matching lines @@
             {
                 "name": "clearBrowserCookies",
                 "description": "Clears browser cookies."
             },
             {
                 "name": "setCacheDisabled",
                 "parameters": [
                     { "name": "cacheDisabled", "type": "boolean", "description": "Cache disabled state." }
                 ],
                 "description": "Toggles ignoring cache for each request. If <code>true</code>, cache will not be used."
+            },  
+            {
+                "name": "loadResourceForFrontend",
+                "async": true,
+                "parameters": [
+                    { "name": "frameId", "$ref": "FrameId", "description": "Frame to load the resource from." },
+                    { "name": "url", "type": "string", "description": "URL of the resource to load." }
+                ],
+                "returns": [
+                    { "name": "content", "type": "string", "description": "Resource content." }
+                ],
+                "description": "Loads a resource in the context of a frame on the inspected page without cross origin checks.",
+                "hidden": true
             }
         ],
         "events": [
             {
                 "name": "requestWillBeSent",
                 "description": "Fired when page is about to send HTTP request.",
                 "parameters": [
                     { "name": "requestId", "$ref": "RequestId", "description": "Request identifier." },
                     { "name": "frameId", "$ref": "FrameId", "description": "Frame identifier.", "hidden": true },
                     { "name": "loaderId", "$ref": "LoaderId", "description": "Loader identifier." },
@@ skipping 2681 matching lines @@
                 ]
             }
         ],
         "events": [
             {
                 "name": "layerTreeDidChange"
             }
         ]
     }]
 }