Remove redundant exports from 'flipper'

Summary: Prevent getRenderHostInstance leaking into 'flipper' types

Reviewed By: lblasa

Differential Revision: D39574678

fbshipit-source-id: 43932d73fed8b37a2a0791a312ee3d5129a4923f

desktop/app/src/index.tsx

@@ -8,4 +8,6 @@
  */
 
 // Ideally we don't want to expose those, but this is for legacy compatibility
-export * from 'flipper-ui-core';
+// It is OK to reference /src/... here as this file i never bundled and only used for typings
+// eslint-disable-next-line no-restricted-imports
+export * from 'flipper-ui-core/src/deprecated-exports';

desktop/flipper-ui-core/src/index.tsx

@@ -7,9 +7,6 @@
  * @format
  */
 
-// TODO: should not be exported anymore, but still needed for 'import from 'flipper'' stuff
-export * from './deprecated-exports';
-
 export {RenderHost, getRenderHostInstance} from 'flipper-frontend-core';
 
 export {startFlipperDesktop} from './startFlipperDesktop';