Plugin folders re-structuring

Summary:
Here I'm changing plugin repository structure to allow re-using of shared packages between both public and fb-internal plugins, and to ensure that public plugins has their own yarn.lock as this will be required to implement reproducible jobs checking plugin compatibility with released flipper versions.

Please note that there are a lot of moved files in this diff, make sure to click "Expand all" to see all that actually changed (there are not much of them actually).

New proposed structure for plugin packages:
```
- root
- node_modules - modules included into Flipper: flipper, flipper-plugin, react, antd, emotion
-- plugins
 --- node_modules - modules used by both public and fb-internal plugins (shared libs will be linked here, see D27034936)
 --- public
---- node_modules - modules used by public plugins
---- pluginA
----- node_modules - modules used by plugin A exclusively
---- pluginB
----- node_modules - modules used by plugin B exclusively
 --- fb
---- node_modules - modules used by fb-internal plugins
---- pluginC
----- node_modules - modules used by plugin C exclusively
---- pluginD
----- node_modules - modules used by plugin D exclusively
```
I've moved all public plugins under dir "plugins/public" and excluded them from root yarn workspaces. Instead, they will have their own yarn workspaces config and yarn.lock and they will use flipper modules as peer dependencies.

Reviewed By: mweststrate

Differential Revision: D27034108

fbshipit-source-id: c2310e3c5bfe7526033f51b46c0ae40199fd7586

desktop/plugins/public/hermesdebuggerrn/index.tsx

@@ -0,0 +1,177 @@
+/**
+ * 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 React from 'react';
+import {
+  FlipperDevicePlugin,
+  Device,
+  styled,
+  colors,
+  FlexRow,
+  FlexColumn,
+} from 'flipper';
+import LaunchScreen from './LaunchScreen';
+import Banner, {isBannerEnabled} from './Banner';
+import SelectScreen from './SelectScreen';
+import ErrorScreen from './ErrorScreen';
+import ChromeDevTools from './ChromeDevTools';
+
+const POLL_SECS = 5 * 1000;
+const METRO_PORT_ENV_VAR = process.env.METRO_SERVER_PORT || '8081';
+const METRO_PORT = isNaN(+METRO_PORT_ENV_VAR) ? '8081' : METRO_PORT_ENV_VAR;
+const METRO_URL = new URL('http://localhost');
+METRO_URL.port = METRO_PORT;
+
+export type Target = Readonly<{
+  id: string;
+  description: string;
+  title: string;
+  faviconUrl: string;
+  devtoolsFrontendUrl: string;
+  type: string;
+  webSocketDebuggerUrl: string;
+  vm: string;
+}>;
+
+export type Targets = ReadonlyArray<Target>;
+
+type State = Readonly<{
+  targets?: Targets | null;
+  selectedTarget?: Target | null;
+  error?: Error | null;
+}>;
+
+const Content = styled(FlexRow)({
+  height: '100%',
+  width: '100%',
+  flexGrow: 1,
+  justifyContent: 'center',
+  alignItems: 'center',
+});
+
+const Container = styled(FlexColumn)({
+  height: '100%',
+  width: '100%',
+  justifyContent: 'flex-start',
+  alignItems: 'flex-start',
+  backgroundColor: colors.light02,
+});
+
+export default class extends FlipperDevicePlugin<State, any, any> {
+  static supportsDevice(device: Device) {
+    return !device.isArchived && device.os === 'Metro';
+  }
+
+  state: State = {
+    targets: null,
+    selectedTarget: null,
+    error: null,
+  };
+
+  poll?: NodeJS.Timeout;
+
+  componentDidMount() {
+    // This is a pretty basic polling mechnaism. We ask Metro every POLL_SECS what the
+    // current available targets are and only handle a few basic state transitions.
+    this.poll = setInterval(this.checkDebugTargets, POLL_SECS);
+    this.checkDebugTargets();
+  }
+
+  componentWillUnmount() {
+    if (this.poll) {
+      clearInterval(this.poll);
+    }
+  }
+
+  checkDebugTargets = () => {
+    fetch(`${METRO_URL.toString()}json`)
+      .then((res) => res.json())
+      .then(
+        (result) => {
+          // We only want to use the Chrome Reload targets.
+          const targets = result.filter(
+            (target: any) =>
+              target.title ===
+              'React Native Experimental (Improved Chrome Reloads)',
+          );
+
+          // Find the currently selected target.
+          // If the current selectedTarget isn't returned, clear it.
+          let currentlySelected = null;
+          if (this.state.selectedTarget != null) {
+            for (const target of result) {
+              if (
+                this.state.selectedTarget?.webSocketDebuggerUrl ===
+                target.webSocketDebuggerUrl
+              ) {
+                currentlySelected = this.state.selectedTarget;
+              }
+            }
+          }
+
+          // Auto-select the first target if there is one,
+          // but don't change the one that's already selected.
+          const selectedTarget =
+            currentlySelected == null && targets.length === 1
+              ? targets[0]
+              : currentlySelected;
+
+          this.setState({
+            error: null,
+            targets,
+            selectedTarget,
+          });
+        },
+        (error) => {
+          this.setState({
+            targets: null,
+            selectedTarget: null,
+            error,
+          });
+        },
+      );
+  };
+
+  handleSelect = (selectedTarget: Target) => this.setState({selectedTarget});
+
+  renderContent() {
+    const {error, selectedTarget, targets} = this.state;
+
+    if (selectedTarget) {
+      let bannerMargin = null;
+      if (isBannerEnabled()) {
+        bannerMargin = '29px';
+      }
+
+      return (
+        <ChromeDevTools
+          url={selectedTarget.devtoolsFrontendUrl}
+          marginTop={bannerMargin}
+        />
+      );
+    } else if (targets != null && targets.length === 0) {
+      return <LaunchScreen />;
+    } else if (targets != null && targets.length > 0) {
+      return <SelectScreen targets={targets} onSelect={this.handleSelect} />;
+    } else if (error != null) {
+      return <ErrorScreen error={error} />;
+    } else {
+      return null;
+    }
+  }
+
+  render() {
+    return (
+      <Container>
+        <Banner />
+        <Content>{this.renderContent()}</Content>
+      </Container>
+    );
+  }
+}