JS: Strip invariant calls in production

Fixes #742

clients/crunchbase/ui/src/data.js

@@ -1,8 +1,20 @@
 // @flow
 
-import {readValue, Struct, makeType, Ref, registerPackage} from 'noms';
+import {
+  invariant,
+  Kind,
+  makeCompoundType,
+  makePrimitiveType,
+  makeType,
+  NomsMap,
+  NomsSet,
+  readValue,
+  Ref,
+  registerPackage,
+  SetLeafSequence,
+  Struct
+} from 'noms';
 import type {ChunkStore, Package} from 'noms';
-import {invariant, Kind, NomsMap, NomsSet, SetLeafSequence, makeCompoundType, makePrimitiveType} from 'noms';
 
 type RoundTypeEnum = 0 | 1 | 2;
 const Seed = 0;

js/src/assert.js

@@ -1,9 +1,8 @@
 // @flow
 
-export function invariant(exp: boolean, message: string = 'Invariant violated') {
-  if (!exp) {
-    throw new Error(message);
-  }
+export function invariant(exp: any, message: string = 'Invariant violated') {
+  if (process.env.NODE_ENV === 'production') return;
+  if (!exp) throw new Error(message);
 }
 
 export function notNull<T>(v: ?T): T {