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 4527 matching lines @@
                 "parameters": [
                     { "name": "x", "type": "integer", "description": "X coordinate of the start of the gesture in CSS pixels." },
                     { "name": "y", "type": "integer", "description": "Y coordinate of the start of the gesture in CSS pixels." },
                     { "name": "duration", "type": "integer", "optional": true, "description": "Duration between touchdown and touchup events in ms (default: 50)." },
                     { "name": "tapCount", "type": "integer", "optional": true, "description": "Number of times to perform the tap (e.g. 2 for double tap, default: 1)." },
                     { "name": "gestureSourceType", "$ref": "GestureSourceType", "optional": true, "description": "Which type of input events to be generated (default: 'default', which queries the platform for the preferred input type)." }
                 ],
                 "description": "Synthesizes a tap gesture over a time period by issuing appropriate touch events.",
                 "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": []
     },
     {
         "domain": "LayerTree",
         "hidden": true,
         "types": [
             {
                 "id": "LayerId",
@@ skipping 592 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"]
             }
         ]
     }]
 }