Use RN Packager to symbolicate stack in redbox

Summary:
See "D3291793 Symbolicate JS stacktrace using RN Packager" for the background
of why this matters. TLDR - saving tons of memory by moving symbolication from
JSC into server and cleaning up old hacks.

Before this change: a redbox causes +73MB JSC size
{F60869250}
{F60869249}

After this change: a redbox causes +1MB JSC size
{F61005061}
{F61005062}

Next step – replace JS implementation by native to show better progress and
clean up even more old APIs (ExceptionsManager.updateExceptionMessage).

Reviewed By: davidaurelio

Differential Revision: D3319151

fbshipit-source-id: 48ff4df27642ea4e1bc2414f48a8dd4d32adee50

Libraries/JavaScriptAppEngine/Initialization/ExceptionsManager.js

@@ -29,23 +29,28 @@ function reportException(e: Error, isFatal: bool) {
       RCTExceptionsManager.reportSoftException(e.message, stack, currentExceptionID);
     }
     if (__DEV__) {
-      require('SourceMapsCache').getSourceMaps().then(sourceMaps => {
-        const prettyStack = parseErrorStack(e, sourceMaps);
-        RCTExceptionsManager.updateExceptionMessage(
-          e.message,
-          prettyStack,
-          currentExceptionID,
-        );
-      })
-      .catch(error => {
-        // This can happen in a variety of normal situations, such as
-        // Network module not being available, or when running locally
-        console.warn('Unable to load source map: ' + error.message);
-      });
+      symbolicateAndUpdateStack(currentExceptionID, e.message, stack);
     }
   }
 }
 
+function symbolicateAndUpdateStack(id, message, stack) {
+  const {fetch} = require('fetch');
+  const {SourceCode, ExceptionsManager} = require('NativeModules');
+  const match = SourceCode.scriptURL && SourceCode.scriptURL.match(/^https?:\/\/.*?\//);
+  const endpoint = (match && match[0] : 'http://localhost:8081/') + 'symbolicate';
+
+  fetch(endpoint, { method: 'POST', body: JSON.stringify({stack}) })
+    .then(response => response.json())
+    .then(response =>
+      ExceptionsManager.updateExceptionMessage(message, response.stack, id))
+    .catch(error => {
+      // This can happen in a variety of normal situations, such as
+      // Network module not being available, or when running locally
+      console.warn('Unable to symbolicate stack trace: ' + error.message);
+    });
+}
+
 /**
  * Logs exceptions to the (native) console and displays them
  */