Move app/src (mostly) to flipper-ui-core/src

Summary:
This diff moves all UI code from app/src to app/flipper-ui-core. That is now slightly too much (e.g. node deps are not removed yet), but from here it should be easier to move things out again, as I don't want this diff to be open for too long to avoid too much merge conflicts.

* But at least flipper-ui-core is Electron free :)
* Killed all cross module imports as well, as they where now even more in the way
* Some unit test needed some changes, most not too big (but emotion hashes got renumbered in the snapshots, feel free to ignore that)
* Found some files that were actually meaningless (tsconfig in plugins, WatchTools files, that start generating compile errors, removed those

Follow up work:
* make flipper-ui-core configurable, and wire up flipper-server-core in Electron instead of here
* remove node deps (aigoncharov)
* figure out correct place to load GKs, plugins, make intern requests etc., and move to the correct module
* clean up deps

Reviewed By: aigoncharov

Differential Revision: D32427722

fbshipit-source-id: 14fe92e1ceb15b9dcf7bece367c8ab92df927a70

desktop/flipper-ui-core/src/reducers/settings.tsx

@@ -0,0 +1,111 @@
+/**
+ * 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 {Actions} from './index';
+import os from 'os';
+import {getRenderHostInstance} from '../RenderHost';
+
+export enum Tristate {
+  True,
+  False,
+  Unset,
+}
+
+export type Settings = {
+  androidHome: string;
+  enableAndroid: boolean;
+  enableIOS: boolean;
+  enablePhysicalIOS: boolean;
+  /**
+   * If unset, this will assume the value of the GK setting.
+   * Note that this setting has no effect in the open source version
+   * of Flipper.
+   */
+  enablePrefetching: Tristate;
+  idbPath: string;
+  jsApps: {
+    webAppLauncher: {
+      url: string;
+      height: number;
+      width: number;
+    };
+  };
+  reactNative: {
+    shortcuts: {
+      enabled: boolean;
+      reload: string;
+      openDevMenu: string;
+    };
+  };
+  darkMode: 'dark' | 'light' | 'system';
+  showWelcomeAtStartup: boolean;
+  suppressPluginErrors: boolean;
+};
+
+export type Action =
+  | {type: 'INIT'}
+  | {
+      type: 'UPDATE_SETTINGS';
+      payload: Settings;
+    };
+
+export const DEFAULT_ANDROID_SDK_PATH = getDefaultAndroidSdkPath();
+
+const initialState: Settings = {
+  androidHome: getDefaultAndroidSdkPath(),
+  enableAndroid: true,
+  enableIOS: os.platform() === 'darwin',
+  enablePhysicalIOS: os.platform() === 'darwin',
+  enablePrefetching: Tristate.Unset,
+  idbPath: '/usr/local/bin/idb',
+  jsApps: {
+    webAppLauncher: {
+      url: 'http://localhost:8888',
+      height: 600,
+      width: 800,
+    },
+  },
+  reactNative: {
+    shortcuts: {
+      enabled: false,
+      reload: 'Alt+Shift+R',
+      openDevMenu: 'Alt+Shift+D',
+    },
+  },
+  darkMode: 'light',
+  showWelcomeAtStartup: true,
+  suppressPluginErrors: false,
+};
+
+export default function reducer(
+  state: Settings = initialState,
+  action: Actions,
+): Settings {
+  if (action.type === 'UPDATE_SETTINGS') {
+    return action.payload;
+  }
+  return state;
+}
+
+export function updateSettings(settings: Settings): Action {
+  return {
+    type: 'UPDATE_SETTINGS',
+    payload: settings,
+  };
+}
+
+function getDefaultAndroidSdkPath() {
+  return os.platform() === 'win32' ? getWindowsSdkPath() : '/opt/android_sdk';
+}
+
+function getWindowsSdkPath() {
+  return `${
+    getRenderHostInstance().paths.homePath
+  }\\AppData\\Local\\android\\sdk`;
+}