Emit a console warning when blocking event listener is delayed for too long

third_party/WebKit/Source/devtools/protocol.json

 {
     "version": { "major": "1", "minor": "1" },
     "domains": [{
         "domain": "Inspector",
         "hidden": true,
         "types": [],
         "commands": [
             {
                 "name": "enable",
                 "description": "Enables inspector domain notifications.",
@@ skipping 455 matching lines @@
                     { "name": "url", "type": "string", "description": "Manifest location." },
                     { "name": "errors", "type": "array", "items": { "$ref": "AppManifestError" } },
                     { "name": "data", "type": "string", "optional": true, "description": "Manifest content." }
                 ],
                 "handlers": ["none"]
             },
             {
                 "name": "requestAppBanner",
                 "hidden": true,
                 "handlers": ["browser"]
+            },
+            {
+                "name": "setBlockedEventsWarningThreshold",
+                "hidden": true,
+                "parameters": [
+                    { "name": "threshold", "type": "number", "description": "If set to a positive number, specifies threshold in seconds for input event latency that will cause a console warning about blocked event to be issued. If zero or less, the warning is disabled." }
+                ]
             }
         ],
         "events": [
             {
                 "name": "domContentEventFired",
                 "parameters": [
                     { "name": "timestamp", "type": "number" }
                 ]
             },
             {
@@ skipping 4664 matching lines @@
                 "parameters": [
                     { "name": "origin", "type": "string", "description": "Security origin." },
                     { "name": "storageTypes", "type": "string", "description": "Comma separated origin names." }
                 ],
                 "description": "Clears storage for origin.",
                 "handlers": ["browser"]
             }
         ]
     }]
 }