Avoid exception when building details for DecodeImage event

Url for this event is retrieved from imageURL field later in the same switch.

BUG=361045

Review URL: https://codereview.chromium.org/339603002

git-svn-id: svn://svn.chromium.org/blink/trunk@176227 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/devtools/front_end/timeline/TracingTimelineUIUtils.js

@@ -163,8 +163,6 @@ WebInspector.TracingTimelineUIUtils.buildDetailsNodeForTraceEvent = function(eve
     case recordType.XHRReadyStateChange:
     case recordType.XHRLoad:
     case recordType.ResourceSendRequest:
-    case recordType.DecodeImage:
-    case recordType.ResizeImage:
         var url = eventData["url"];
         if (url)
             detailsText = WebInspector.displayNameForURL(url);