Yarn workspaces

Summary:
1) moved "sonar/desktop/src" to "sonar/desktop/app/src", so "app" is now a separate package containing the core Flipper app code
2) Configured yarn workspaces with the root in "sonar/desktop": app, static, pkg, doctor, headless-tests. Plugins are not included for now, I plan to do this later.

Reviewed By: jknoxville

Differential Revision: D20535782

fbshipit-source-id: 600b2301960f37c7d72166e0d04eba462bec9fc1

desktop/app/src/dispatcher/desktopDevice.tsx

@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import {Store} from '../reducers/index';
+import {Logger} from '../fb-interfaces/Logger';
+
+import MacDevice from '../devices/MacDevice';
+import WindowsDevice from '../devices/WindowsDevice';
+
+export default (store: Store, _logger: Logger) => {
+  let device;
+  if (process.platform === 'darwin') {
+    device = new MacDevice();
+  } else if (process.platform === 'win32') {
+    device = new WindowsDevice();
+  } else {
+    return;
+  }
+  device.loadDevicePlugins(store.getState().plugins.devicePlugins);
+  store.dispatch({
+    type: 'REGISTER_DEVICE',
+    payload: device,
+  });
+};