Bug 210168

Uncaught Exception in Web Inspector. Steps to Reproduce: 1. inspect any page with content that doesn't auto-format/pretty-print 2. inspect the inspector 3. set a breakpoint in the constructor of `WI.FormatterContentBuilder` 4. auto-format/pretty-print a resource Also throws when selecting a frame Uncaught Exceptions: ----------------------- - undefined is not an object (evaluating 'this._target.NetworkAgent.getResponseBody') (at Resource.js:851:45) requestContentFromBackend @ Resource.js:851:45 requestContent @ SourceCode.js:173:100 _tryEnableCustomResponseContentViews @ ResourceClusterContentView.js:504:38 ResourceClusterContentView @ ResourceClusterContentView.js:59:50 createFromRepresentedObject @ ContentView.js:52:53 contentViewForRepresentedObject @ ContentView.js:214:72 showContentViewForRepresentedObject @ ContentBrowser.js:151:63 showRepresentedObject @ ContentBrowserTabContentView.js:225:64 ? @ Main.js:1427:41 ? @ Main.js:1472:29 ? @ Main.js:1477:22 _handleTreeSelectionDidChange @ SourcesNavigationSidebarPanel.js:1849:42 dispatch @ Object.js:165:30 dispatchEventToListeners @ Object.js:172:17 _dispatchSelectionDidChangeEvent @ TreeOutline.js:1133:38 selectionControllerSelectionDidChange @ TreeOutline.js:805:46 _updateSelectedItems @ SelectionController.js:392:65 selectItem @ SelectionController.js:97:34 selectedTreeElement @ TreeOutline.js:160:49 selectTreeElementInternal @ TreeOutline.js:895:13 select @ TreeElement.js:543:46 refresh @ ThreadTreeElement.js:67:46 _handleDebuggerCallFramesDidChange @ SourcesNavigationSidebarPanel.js:2288:32 dispatch @ Object.js:165:30 dispatchEventToListeners @ Object.js:172:17 debuggerDidPause @ DebuggerManager.js:830:38 paused @ DebuggerObserver.js:71:44 _dispatchEvent @ Connection.js:210:26 dispatch @ Connection.js:79:32 dispatchMessageFromWorker @ WorkerManager.js:76:28 dispatchMessageFromWorker @ WorkerObserver.js:42:51 _dispatchEvent @ Connection.js:210:26 dispatch @ Connection.js:79:32 dispatchMessageFromTarget @ TargetManager.js:176:39 dispatchMessageFromTarget @ TargetObserver.js:47:51 _dispatchEvent @ Connection.js:210:26 dispatch @ Connection.js:79:32 dispatch @ InspectorBackend.js:219:52 ? @ MessageDispatcher.js:42:34 Additional Details: cause --> An uncaught exception was thrown while handling event: Debugger.paused ----------------------- Notes: Inspected URL: file:///Volumes/DATA/Build/Debug/WebInspectorUI.framework/Resources/Main.html Loading completed: true Frontend User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/605.1.15 (KHTML, like Gecko) Dispatch Source: Protocol Event Protocol Event: {"method":"Debugger.paused","params":{"callFrames":[{"callFrameId":"{\"ordinal\":0,\"injectedScriptId\":1}","functionName":"FormatterContentBuilder","location":{"scriptId":"689","lineNumber":30,"columnNumber":8},"scopeChain":[{"object":{"type":"object","objectId":"{\"injectedScriptId\":1,\"id\":1}","className":"JSLexicalEnvironment","description":"JSLexicalEnvironment"},"type":"closure","name":"FormatterContentBuilder","location":{"scriptId":"689","lineNumber":29,"columnNumber":16}},{"object":{"…