Restructure background script (#70)

Splits some background script functionality into separate modules:
 - Receiver selector handling is moved to ./SelectorManager.
 - Status bridge handling is moved to ./StatusManager.
 - Menu creation and updates are handled in ./createMenus.
 - Shim creation is handled in ./createShim.

TypedEventTarget allows EventTarget-derived classes to export typed events.

Options type definition is moved to ./lib/options, module assumes more responsibility for update handling and provides a "changed" event.

Private cast._requestSession method allows bypassing receiver selector.

ext/src/ui/options/Bridge.tsx

@@ -7,7 +7,7 @@ import semver from "semver";
 import { getNextEllipsis
        , getWindowCenteredProps } from "../../lib/utils";
 
-import { BridgeInfo } from "../../lib/getBridgeInfo";
+import { BridgeInfo } from "../../lib/bridge";
 
 const _ = browser.i18n.getMessage;
 

ext/src/ui/options/index.tsx

@@ -4,13 +4,13 @@
 import React, { Component } from "react";
 import ReactDOM from "react-dom";
 
-import defaultOptions, { Options } from "../../defaultOptions";
+import defaultOptions from "../../defaultOptions";
 
 import Bridge from "./Bridge";
 import EditableList from "./EditableList";
 
-import getBridgeInfo, { BridgeInfo } from "../../lib/getBridgeInfo";
-import options from "../../lib/options";
+import bridge, { BridgeInfo } from "../../lib/bridge";
+import options, { Options } from "../../lib/options";
 import { REMOTE_MATCH_PATTERN_REGEX } from "../../lib/utils";
 
 import { ReceiverSelectorType } from "../../receiver_selectors";
@@ -88,7 +88,7 @@ class OptionsApp extends Component<{}, OptionsAppState> {
           , options: await options.getAll()
         });
 
-        const bridgeInfo = await getBridgeInfo();
+        const bridgeInfo = await bridge.getInfo();
         const { os } = await browser.runtime.getPlatformInfo();
 
         this.setState({
@@ -350,17 +350,8 @@ class OptionsApp extends Component<{}, OptionsAppState> {
         this.form.reportValidity();
 
         try {
-            const oldOpts = await options.getAll();
             await options.setAll(this.state.options);
 
-            const alteredOptions = [];
-            for (const [ key, val ] of Object.entries(this.state.options)) {
-                const oldVal = oldOpts[key];
-                if (oldVal !== val) {
-                    alteredOptions.push(key);
-                }
-            }
-
             this.setState({
                 hasSaved: true
             }, () => {
@@ -370,12 +361,6 @@ class OptionsApp extends Component<{}, OptionsAppState> {
                     });
                 }, 1000);
             });
-
-            // Send update message / event
-            browser.runtime.sendMessage({
-                subject: "optionsUpdated"
-              , data: { alteredOptions }
-            });
         } catch (err) {
             console.error("Failed to save options");
         }
@@ -421,7 +406,7 @@ class OptionsApp extends Component<{}, OptionsAppState> {
             bridgeLoading: true
         });
 
-        const bridgeInfo = await getBridgeInfo();
+        const bridgeInfo = await bridge.getInfo();
 
         this.setState({
             bridgeInfo

ext/src/ui/popup/index.tsx

@@ -179,11 +179,6 @@ class PopupApp extends Component<{}, PopupAppState> {
             try {
                 const filePath = window.prompt();
 
-                // Validate URL
-                const fileUrl = new URL(filePath.startsWith("file://")
-                    ? filePath
-                    : `file://${filePath}`);
-
                 this.setState({
                     mediaType
                   , filePath