[DevTools] Make most fields of ExceptionDetails non-optional.

third_party/WebKit/Source/platform/v8_inspector/js_protocol.json

 {
     "version": { "major": "1", "minor": "1" },
     "domains": [{
         "domain": "Runtime",
         "description": "Runtime domain exposes JavaScript runtime by means of remote evaluation and mirror objects. Evaluation results are returned as mirror object that expose object type, string representation and unique identifier that can be used for further object reference. Original objects are maintained in memory unless they are either explicitly released or are released along with the other objects in their object group.",
         "types": [
             {
                 "id": "ScriptId",
                 "type": "string",
                 "description": "Unique script identifier."
@@ skipping 116 matching lines @@
                     { "name": "isDefault", "type": "boolean", "description": "Whether context is the default page context (as opposite to e.g. context of content script).", "hidden": true },
                     { "name": "origin", "type": "string", "description": "Execution context origin.", "hidden": true},
                     { "name": "name", "type": "string", "description": "Human readable name describing given context.", "hidden": true},
                     { "name": "frameId", "type": "string", "description": "Id of the owning frame. May be an empty string if the context is not associated with a frame." }
                 ]
             },
             {
                 "id": "ExceptionDetails",
                 "type": "object",
                 "hidden": true,
-                "description": "Detailed information on exception (or error) that was thrown during script compilation or execution.",
+                "description": "Detailed information about exception (or error) that was thrown during script compilation or execution.",
                 "properties": [
                     { "name": "text", "type": "string", "description": "Exception text." },
-                    { "name": "url", "type": "string", "optional": true, "description": "URL of the message origin." },
-                    { "name": "scriptId", "type": "string", "optional": true, "description": "Script ID of the message origin." },
-                    { "name": "lineNumber", "type": "integer", "optional": true, "description": "Line number in the resource that generated this message. (0-based)." },
-                    { "name": "columnNumber", "type": "integer", "optional": true, "description": "Column number in the resource that generated this message. (0-based)." },
-                    { "name": "stack", "$ref": "StackTrace", "optional": true, "description": "JavaScript stack trace for assertions and error messages." }
+                    { "name": "scriptId", "$ref": "ScriptId", "description": "Script ID of the exception location." },
+                    { "name": "lineNumber", "type": "integer", "description": "Line number of the exception location (0-based)." },
+                    { "name": "columnNumber", "type": "integer", "description": "Column number of the exception location (0-based)." },
+                    { "name": "url", "type": "string", "optional": true, "description": "URL of the exception location, to be used when the script was not reported." },
+                    { "name": "stackTrace", "$ref": "StackTrace", "optional": true, "description": "JavaScript stack trace if available." }
                 ]
             },
             {
                 "id": "CallFrame",
                 "type": "object",
                 "description": "Stack entry for runtime errors and assertions.",
                 "properties": [
                     { "name": "functionName", "type": "string", "description": "JavaScript function name." },
                     { "name": "scriptId", "$ref": "ScriptId", "description": "JavaScript script id." },
                     { "name": "url", "type": "string", "description": "JavaScript script name or url." },
@@ skipping 837 matching lines @@
             {
                 "name": "heapStatsUpdate",
                 "description": "If heap objects tracking has been started then backend may send update for one or more fragments",
                 "parameters": [
                     { "name": "statsUpdate", "type": "array", "items": { "type": "integer" }, "description": "An array of triplets. Each triplet describes a fragment. The first integer is the fragment index, the second integer is a total count of objects for the fragment, the third integer is a total size of the objects for the fragment."}
                 ]
             }
         ]
     }]
 }