fix(bundlesize): Reduced overall size by around 0.5kB (#313)

The goal here is to reduce the bundlesize as much as possible while not creating breaking changes to the typescript library definitions, nor breaking the spec or any other regressions.

Author: stipsan

package.json

@@ -28,10 +28,10 @@
     "build:umd.min": "BABEL_ENV=umd NODE_ENV=production rollup -c -f umd -o umd/scroll-into-view-if-needed.min.js",
     "clean": "rimraf 'umd' 'es' 'typings'",
     "precommit": "lint-staged",
-    "dev": "concurrently 'tsc --watch' 'yarn build:cjs --watch'",
+    "dev": "concurrently 'tsc --noEmit --watch' 'tsc --noEmit -p tests/typescript --watch' 'yarn build:cjs --watch' 'yarn build:es --watch' 'yarn build:umd --watch' 'yarn build:umd.min --watch'",
     "lint": "eslint ./integration-examples",
     "prepublishOnly": "unset npm_config_cafile && yarn build",
-    "typecheck": "tsc --noEmit"
+    "typecheck": "tsc --noEmit && tsc --noEmit -p tests/typescript"
   },
   "devDependencies": {
     "@babel/cli": "7.0.0-beta.51",