Fix symbolication outside of chrome debugging

Summary:
When debugging in VScode or nucleide using a nodejs environment rather than chrome, the JS sources are made to appear as if they exist on disk, rather than coming from a `http://` url. Prior to this change the packager would see these file paths and not know how to handle them.

Since all the application JS will be part of a bundle file, we can switch out the path to the bundle on the filesystem with paths to the bundle served by the packager, and things will work just as though it was debugging in chrome. We stop the replacement once we reach an internal module (`vm.js` in the case of both nucleide and VSCode) since that is the point when the execution switches from inside the app to the surrounding debugging environment.

I've verified that this fixes redbox stack trace symbolication in VSCode, and from my understanding of nucleide's debugging environment it should also work there without requiring any changes.
Closes https://github.com/facebook/react-native/pull/9906

Differential Revision: D3887166

Pulled By: davidaurelio

fbshipit-source-id: e3a6704f30e0fd045ad836bba51f6e20d9854c30

Libraries/JavaScriptAppEngine/Initialization/symbolicateStackTrace.js

@@ -13,6 +13,7 @@
 
 const {fetch} = require('fetch');
 const getDevServer = require('getDevServer');
+const {SourceCode} = require('NativeModules');
 
 import type {StackFrame} from 'parseErrorStack';
 
@@ -21,6 +22,19 @@ async function symbolicateStackTrace(stack: Array<StackFrame>): Promise<Array<St
   if (!devServer.bundleLoadedFromServer) {
     throw new Error('Bundle was not loaded from the packager');
   }
+  if (SourceCode.scriptURL) {
+    for (let i = 0; i < stack.length; ++i) {
+      // If the sources exist on disk rather than appearing to come from the packager,
+      // replace the location with the packager URL until we reach an internal source
+      // which does not have a path (no slashes), indicating a switch from within
+      // the application to a surrounding debugging environment.
+      if (/^http/.test(stack[i].file) || !/[\\/]/.test(stack[i].file)) {
+        break;
+      }
+      stack[i].file = SourceCode.scriptURL;
+    }
+  }
+
   const response = await fetch(devServer.url + 'symbolicate', {
     method: 'POST',
     body: JSON.stringify({stack}),