ref: Remove rollup-modify-plugin as we dont use it anymore

Author: kamilogorek

packages/browser/package.json

@@ -43,7 +43,6 @@
     "rollup": "^1.10.1",
     "rollup-plugin-commonjs": "^9.3.4",
     "rollup-plugin-license": "^0.8.1",
-    "rollup-plugin-modify": "^3.0.0",
     "rollup-plugin-node-resolve": "^4.2.3",
     "rollup-plugin-terser": "^4.0.4",
     "rollup-plugin-typescript2": "^0.21.0",

packages/browser/rollup.config.js

@@ -3,7 +3,6 @@ import typescript from 'rollup-plugin-typescript2';
 import license from 'rollup-plugin-license';
 import resolve from 'rollup-plugin-node-resolve';
 import commonjs from 'rollup-plugin-commonjs';
-import modify from 'rollup-plugin-modify';
 
 const commitHash = require('child_process')
   .execSync('git rev-parse --short HEAD', { encoding: 'utf-8' })
@@ -47,11 +46,6 @@ const plugins = [
     mainFields: ['module'],
   }),
   commonjs(),
-  modify({
-    // It's very difficult to use Symbol without polyfilling in IE10 and still making TypeScript behave correctly.
-    // Just remove it and leave this space in there, so that SourceMaps are still correct.
-    "this[Symbol.toStringTag] = '[object SyncPromise]';": ' ',
-  }),
 ];
 
 const bundleConfig = {