React: Upgrade to react-devtools@3.3.4

Summary:
Upgrades `react-devtools` for React Native and Nuclide to v3.3.4.

Notably, this brings working support for the React Profiler!

Reviewed By: bvaughn

Differential Revision: D9721317

fbshipit-source-id: 898666d12a33d8b874fcb133e9353f483285edc2

package.json

@@ -188,7 +188,7 @@
     "promise": "^7.1.1",
     "prop-types": "^15.5.8",
     "react-clone-referenced-element": "^1.0.1",
-    "react-devtools-core": "3.3.2",
+    "react-devtools-core": "3.3.4",
     "react-timer-mixin": "^0.13.2",
     "regenerator-runtime": "^0.11.0",
     "rimraf": "^2.5.4",