Use set instead of array to keep list of supported plugins per client

Summary: Use set instead of array to keep list of supported plugins per client. It is not used as array anyway, in most places it is used to determine whether a plugin is supported or not and it's much faster to use set for that.

Reviewed By: priteshrnandgaonkar

Differential Revision: D29200673

fbshipit-source-id: 5f3c404a1a668c153867d7c1b6c223941f0b3b36

desktop/app/src/test-utils/MockFlipper.tsx

@@ -181,7 +181,7 @@ export default class MockFlipper {
       device.isArchived ? null : createStubConnection(),
       this._logger,
       this._store,
-      supportedPlugins,
+      new Set(supportedPlugins),
       device,
     );
     // yikes