Remove instanceof checks

Summary: Replaced `instanceof` checks with `isSandyPlugin` utility. That is cleaner to read and makes it easier to find places where we make exceptions for Sandy plugins

Reviewed By: jknoxville

Differential Revision: D22206707

fbshipit-source-id: b44a1b585424f3b9bf0d7ce200c34107f03ed55e

desktop/app/src/utils/messageQueue.tsx

@@ -7,7 +7,11 @@
  * @format
  */
 
-import {PersistedStateReducer, FlipperDevicePlugin} from '../plugin';
+import {
+  PersistedStateReducer,
+  FlipperDevicePlugin,
+  isSandyPlugin,
+} from '../plugin';
 import {State, MiddlewareAPI} from '../reducers/index';
 import {setPluginState} from '../reducers/pluginStates';
 import {flipperRecorderAddEvent} from './pluginStateRecorder';
@@ -200,7 +204,8 @@ export function processMessagesLater(
     | SandyPluginDefinition,
   messages: Message[],
 ) {
-  if (plugin instanceof SandyPluginDefinition) {
+  // @ts-ignore
+  if (isSandyPlugin(plugin)) {
     // TODO:
     throw new Error(
       'Receiving messages is not yet supported for Sandy plugins',