Correctly handle object classname and add Symbol type to PropertyPreview and CallArgument in the pr…

Source/devtools/protocol.json

 {
     "version": { "major": "1", "minor": "1" },
     "domains": [{
         "domain": "Inspector",
         "hidden": true,
         "types": [],
         "commands": [
             {
                 "name": "enable",
                 "description": "Enables inspector domain notifications."
@@ skipping 669 matching lines @@
                     { "name": "overflow", "type": "boolean", "description": "True iff some of the properties of the original did not fit." },
                     { "name": "properties", "type": "array", "items": { "$ref": "PropertyPreview" }, "description": "List of the properties." }
                 ]
             },
             {
                 "id": "PropertyPreview",
                 "type": "object",
                 "hidden": true,
                 "properties": [
                     { "name": "name", "type": "string", "description": "Property name." },
-                        { "name": "type", "type": "string", "enum": ["object", "function", "undefined", "string", "number", "boolean", "accessor"], "description": "Object type. Accessor means that the property itself is an accessor property." },
-                        { "name": "value", "type": "string", "optional": true, "description": "User-friendly property value string." },
-                        { "name": "valuePreview", "$ref": "ObjectPreview", "optional": true, "description": "Nested value preview." },
-                        { "name": "subtype", "type": "string", "optional": true, "enum": ["array", "null", "node", "regexp", "date"], "description": "Object subtype hint. Specified for <code>object</code> type values only." }
+                    { "name": "type", "type": "string", "enum": ["object", "function", "undefined", "string", "number", "boolean", "symbol", "accessor"], "description": "Object type. Accessor means that the property itself is an accessor property." },
+                    { "name": "value", "type": "string", "optional": true, "description": "User-friendly property value string." },
+                    { "name": "valuePreview", "$ref": "ObjectPreview", "optional": true, "description": "Nested value preview." },
+                    { "name": "subtype", "type": "string", "optional": true, "enum": ["array", "null", "node", "regexp", "date"], "description": "Object subtype hint. Specified for <code>object</code> type values only." }
                 ]
             },
             {
                 "id": "PropertyDescriptor",
                 "type": "object",
                 "description": "Object property descriptor.",
                 "properties": [
                     { "name": "name", "type": "string", "description": "Property name." },
                     { "name": "value", "$ref": "RemoteObject", "optional": true, "description": "The value associated with the property." },
                     { "name": "writable", "type": "boolean", "optional": true, "description": "True if the value associated with the property may be changed (data descriptors only)." },
@@ skipping 16 matching lines @@
                 ],
                 "hidden": true
             },
             {
                 "id": "CallArgument",
                 "type": "object",
                 "description": "Represents function call argument. Either remote object id <code>objectId</code> or primitive <code>value</code> or neither of (for undefined) them should be specified.",
                 "properties": [
                     { "name": "value", "type": "any", "optional": true, "description": "Primitive value, or description string if the value can not be JSON-stringified (like NaN, Infinity, -Infinity, -0)." },
                     { "name": "objectId", "$ref": "RemoteObjectId", "optional": true, "description": "Remote object handle." },
-                    { "name": "type", "optional": true, "hidden": true, "type": "string", "enum": ["object", "function", "undefined", "string", "number", "boolean"], "description": "Object type." }
+                    { "name": "type", "optional": true, "hidden": true, "type": "string", "enum": ["object", "function", "undefined", "string", "number", "boolean", "symbol"], "description": "Object type." }
                 ]
             },
             {
                 "id": "ExecutionContextId",
                 "type": "integer",
                 "description": "Id of an execution context."
             },
             {
                 "id": "ExecutionContextDescription",
                 "type": "object",
@@ skipping 3404 matching lines @@
             {
                 "name": "dataAvailable",
                 "parameters": [
                     {"name": "value", "type": "array", "items": { "$ref": "PowerEvent" }, "description": "List of power events." }
                 ],
                 "handlers": ["browser", "frontend"]
             }
         ]
     }]
 }