Don't throw if selectedPlugin doesn't exist

Summary:
When a plugin was selected the last time Flipper was running, but is not available anymore, Flipper was still trying to load the plugin and failed.

Now, if the selected plugin is not available, we just don't render anything.

Reviewed By: jknoxville

Differential Revision: D14854930

fbshipit-source-id: 9ddec47becce7bffcf93b3f4a092a8fcf2022f4f

src/PluginContainer.js

@@ -39,13 +39,6 @@ const SidebarContainer = styled(FlexRow)({
   overflow: 'scroll',
 });
 
-/*
-pluginState: pluginStates[pluginKey],
-activePlugin,
-target,
-deepLinkPayload,
-pluginKey,
-*/
 type OwnProps = {|
   logger: Logger,
 |};
@@ -55,7 +48,7 @@ type Props = {|
   pluginState: Object,
   activePlugin: ?Class<FlipperPlugin<> | FlipperDevicePlugin<>>,
   target: Client | BaseDevice | null,
-  pluginKey: string,
+  pluginKey: ?string,
   deepLinkPayload: ?string,
 
   selectPlugin: (payload: {|
@@ -95,7 +88,8 @@ class PluginContainer extends PureComponent<Props> {
       target,
       isArchivedDevice,
     } = this.props;
-    if (!activePlugin || !target) {
+    if (!activePlugin || !target || !pluginKey) {
+      console.warn(`No selected plugin. Rendering empty!`);
       return null;
     }
     const props: PluginProps<Object> = {
@@ -158,7 +152,7 @@ export default connect<Props, OwnProps, _, _, _, _>(
     pluginStates,
     plugins: {devicePlugins, clientPlugins},
   }) => {
-    let pluginKey = 'unknown';
+    let pluginKey = null;
     let target = null;
     let activePlugin: ?Class<FlipperPlugin<> | FlipperDevicePlugin<>> = null;
 
@@ -174,12 +168,9 @@ export default connect<Props, OwnProps, _, _, _, _>(
       } else {
         target = clients.find((client: Client) => client.id === selectedApp);
         activePlugin = clientPlugins.get(selectedPlugin);
-        if (!activePlugin || !target) {
-          throw new Error(
-            `Plugin "${selectedPlugin || ''}" could not be found.`,
-          );
+        if (activePlugin && target) {
+          pluginKey = getPluginKey(target.id, activePlugin.id);
         }
-        pluginKey = getPluginKey(target.id, activePlugin.id);
       }
     }
     const isArchivedDevice = !selectedDevice