Reorganize module loading.

We now use webpack instead of SystemJS, effectively bundling modules
into one file (plus commons chunks) for every entry point.  This results
in a much smaller extension size (almost half).  Furthermore we use
yarn/npm even for extension run-time dependencies.  This relieves us
from manually vendoring and building dependencies.  It's also easier to
understand for new developers familiar with node.

3 files changed, 173 insertions, 88 deletions

diff --git a/node_modules/selenium-webdriver/firefox/binary.js b/node_modules/selenium-webdriver/firefox/binary.js
index b997b480d..a1360bab7 100644
--- a/node_modules/selenium-webdriver/firefox/binary.js
+++ b/node_modules/selenium-webdriver/firefox/binary.js
@@ -47,27 +47,17 @@ const NO_FOCUS_LIB_AMD64 = isDevMode ?
 const X_IGNORE_NO_FOCUS_LIB = 'x_ignore_nofocus.so';
 
 
-let foundBinary = null;
-let foundDevBinary = null;
-
-
 /**
- * Checks the default Windows Firefox locations in Program Files.
- *
- * @param {boolean=} opt_dev Whether to find the Developer Edition.
+ * @param {string} file Path to the file to find, relative to the program files
+ *     root.
  * @return {!Promise<?string>} A promise for the located executable.
  *     The promise will resolve to {@code null} if Firefox was not found.
  */
-function defaultWindowsLocation(opt_dev) {
-  var files = [
+function findInProgramFiles(file) {
+  let files = [
     process.env['PROGRAMFILES'] || 'C:\\Program Files',
     process.env['PROGRAMFILES(X86)'] || 'C:\\Program Files (x86)'
-  ].map(function(prefix) {
-    if (opt_dev) {
-      return path.join(prefix, 'Firefox Developer Edition\\firefox.exe');
-    }
-    return path.join(prefix, 'Mozilla Firefox\\firefox.exe');
-  });
+  ].map(prefix => path.join(prefix, file));
   return io.exists(files[0]).then(function(exists) {
     return exists ? files[0] : io.exists(files[1]).then(function(exists) {
       return exists ? files[1] : null;
@@ -77,49 +67,104 @@ function defaultWindowsLocation(opt_dev) {
 
 
 /**
- * Locates the Firefox binary for the current system.
+ * Provides methods for locating the executable for a Firefox release channel
+ * on Windows and MacOS. For other systems (i.e. Linux), Firefox will always
+ * be located on the system PATH.
  *
- * @param {boolean=} opt_dev Whether to find the Developer Edition. This only
- *     used on Windows and OSX.
- * @return {!Promise<string>} A promise for the located binary. The promise will
- *     be rejected if Firefox cannot be located.
+ * @final
  */
-function findFirefox(opt_dev) {
-  if (opt_dev && foundDevBinary) {
-    return foundDevBinary;
+class Channel {
+  /**
+   * @param {string} darwin The path to check when running on MacOS.
+   * @param {string} win32 The path to check when running on Windows.
+   */
+  constructor(darwin, win32) {
+    /** @private @const */ this.darwin_ = darwin;
+    /** @private @const */ this.win32_ = win32;
+    /** @private {Promise<string>} */
+    this.found_ = null;
   }
 
-  if (!opt_dev && foundBinary) {
-    return foundBinary;
+  /**
+   * Attempts to locate the Firefox executable for this release channel. This
+   * will first check the default installation location for the channel before
+   * checking the user's PATH. The returned promise will be rejected if Firefox
+   * can not be found.
+   *
+   * @return {!Promise<string>} A promise for the location of the located
+   *     Firefox executable.
+   */
+  locate() {
+    if (this.found_) {
+      return this.found_;
+    }
+
+    let found;
+    switch (process.platform) {
+      case 'darwin':
+        found = io.exists(this.darwin_)
+            .then(exists => exists ? this.darwin_ : io.findInPath('firefox'));
+        break;
+
+      case 'win32':
+        found = findInProgramFiles(this.win32_)
+            .then(found => found || io.findInPath('firefox.exe'));
+        break;
+
+      default:
+        found = Promise.resolve(io.findInPath('firefox'));
+        break;
+    }
+
+    this.found_ = found.then(found => {
+      if (found) {
+        // TODO: verify version info.
+        return found;
+      }
+      throw Error('Could not locate Firefox on the current system');
+    });
+    return this.found_;
   }
+}
 
-  let found;
-  if (process.platform === 'darwin') {
-    let exe = opt_dev
-        ? '/Applications/FirefoxDeveloperEdition.app/Contents/MacOS/firefox-bin'
-        : '/Applications/Firefox.app/Contents/MacOS/firefox-bin';
-    found = io.exists(exe).then(exists => exists ? exe : null);
 
-  } else if (process.platform === 'win32') {
-    found = defaultWindowsLocation(opt_dev);
+/**
+ * Firefox's developer channel.
+ * @const
+ * @see <https://www.mozilla.org/en-US/firefox/channel/desktop/#aurora>
+ */
+Channel.AURORA = new Channel(
+  '/Applications/FirefoxDeveloperEdition.app/Contents/MacOS/firefox-bin',
+  'Firefox Developer Edition\\firefox.exe');
 
-  } else {
-    found = Promise.resolve(io.findInPath('firefox'));
-  }
+/**
+ * Firefox's beta channel. Note this is provided mainly for convenience as
+ * the beta channel has the same installation location as the main release
+ * channel.
+ * @const
+ * @see <https://www.mozilla.org/en-US/firefox/channel/desktop/#beta>
+ */
+Channel.BETA = new Channel(
+  '/Applications/Firefox.app/Contents/MacOS/firefox-bin',
+  'Mozilla Firefox\\firefox.exe');
 
-  found = found.then(found => {
-    if (found) {
-      return found;
-    }
-    throw Error('Could not locate Firefox on the current system');
-  });
+/**
+ * Firefox's release channel.
+ * @const
+ * @see <https://www.mozilla.org/en-US/firefox/desktop/>
+ */
+Channel.RELEASE = new Channel(
+  '/Applications/Firefox.app/Contents/MacOS/firefox-bin',
+  'Mozilla Firefox\\firefox.exe');
 
-  if (opt_dev) {
-    return foundDevBinary = found;
-  } else {
-    return foundBinary = found;
-  }
-}
+/**
+ * Firefox's nightly release channel.
+ * @const
+ * @see <https://www.mozilla.org/en-US/firefox/channel/desktop/#nightly>
+ */
+Channel.NIGHTLY = new Channel(
+  '/Applications/FirefoxNightly.app/Contents/MacOS/firefox-bin',
+  'Nightly\\firefox.exe');
 
 
 /**
@@ -151,20 +196,23 @@ function installNoFocusLibs(profileDir) {
  * use with WebDriver.
  *
  * If created _without_ a path for the Firefox binary to use, this class will
- * attempt to find Firefox when {@link #launch()} is called. For OSX and
+ * attempt to find Firefox when {@link #launch()} is called. For MacOS and
  * Windows, this class will look for Firefox in the current platform's default
- * installation location (e.g. /Applications/Firefox.app on OSX). For all other
- * platforms, the Firefox executable must be available on your system `PATH`.
+ * installation location (e.g. /Applications/Firefox.app on MacOS). For all
+ * other platforms, the Firefox executable must be available on your system
+ * `PATH`.
  *
  * @final
  */
 class Binary {
   /**
-   * @param {string=} opt_exe Path to the Firefox binary to use.
+   * @param {?(string|Channel)=} opt_exeOrChannel Either the path to a specific
+   *     Firefox binary to use, or a {@link Channel} instance that describes
+   *     how to locate the desired Firefox version.
    */
-  constructor(opt_exe) {
-    /** @private {(string|undefined)} */
-    this.exe_ = opt_exe;
+  constructor(opt_exeOrChannel) {
+    /** @private {?(string|Channel)} */
+    this.exe_ = opt_exeOrChannel || null;
 
     /** @private {!Array.<string>} */
     this.args_ = [];
@@ -187,7 +235,7 @@ class Binary {
    *     on the current system.
    */
   getExe() {
-    return this.exe_;
+    return typeof this.exe_ === 'string' ? this.exe_ : undefined;
   }
 
   /**
@@ -223,6 +271,8 @@ class Binary {
    *
    * @param {boolean=} opt_use Whether to use the developer edition. Defaults to
    *     true.
+   * @deprecated Use the {@link Channel} class to indicate the desired Firefox
+   *     version when creating a new binary: `new Binary(Channel.AURORA)`.
    */
   useDevEdition(opt_use) {
     this.devEdition_ = opt_use === undefined || !!opt_use;
@@ -238,7 +288,13 @@ class Binary {
    *     used by this instance.
    */
   locate() {
-    return Promise.resolve(this.exe_ || findFirefox(this.devEdition_));
+    if (typeof this.exe_ === 'string') {
+      return Promise.resolve(this.exe_);
+    } else if (this.exe_ instanceof Channel) {
+      return this.exe_.locate();
+    }
+    let channel = this.devEdition_ ? Channel.AURORA : Channel.RELEASE;
+    return channel.locate();
   }
 
   /**
@@ -284,4 +340,5 @@ class Binary {
 
 
 exports.Binary = Binary;
+exports.Channel = Channel;
 
diff --git a/node_modules/selenium-webdriver/firefox/extension.js b/node_modules/selenium-webdriver/firefox/extension.js
index 60abb06b8..3bda759a7 100644
--- a/node_modules/selenium-webdriver/firefox/extension.js
+++ b/node_modules/selenium-webdriver/firefox/extension.js
@@ -161,7 +161,7 @@ function readManifest(addonPath) {
     manifest = io.stat(addonPath).then(function(stats) {
       if (!stats.isDirectory()) {
         throw Error(
-            'Add-on path is niether a xpi nor a directory: ' + addonPath);
+            'Add-on path is neither a xpi nor a directory: ' + addonPath);
       }
       return io.read(path.join(addonPath, 'install.rdf'));
     });
diff --git a/node_modules/selenium-webdriver/firefox/index.js b/node_modules/selenium-webdriver/firefox/index.js
index 4ea1702a9..d5c88274a 100644
--- a/node_modules/selenium-webdriver/firefox/index.js
+++ b/node_modules/selenium-webdriver/firefox/index.js
@@ -26,28 +26,31 @@
  *
  * __Customizing the Firefox Profile__
  *
- * The {@link Profile} class may be used to configure the browser profile used
- * with WebDriver, with functions to install additional
+ * The {@linkplain Profile} class may be used to configure the browser profile
+ * used with WebDriver, with functions to install additional
  * {@linkplain Profile#addExtension extensions}, configure browser
  * {@linkplain Profile#setPreference preferences}, and more. For example, you
  * may wish to include Firebug:
  *
- *     var firefox = require('selenium-webdriver/firefox');
+ *     const {Builder} = require('selenium-webdriver');
+ *     const firefox = require('selenium-webdriver/firefox');
  *
- *     var profile = new firefox.Profile();
+ *     let profile = new firefox.Profile();
  *     profile.addExtension('/path/to/firebug.xpi');
  *     profile.setPreference('extensions.firebug.showChromeErrors', true);
  *
- *     var options = new firefox.Options().setProfile(profile);
- *     var driver = new firefox.Driver(options);
+ *     let options = new firefox.Options().setProfile(profile);
+ *     let driver = new Builder()
+ *         .forBrowser('firefox')
+ *         .setFirefoxOptions(options)
+ *         .build();
  *
- * The {@link Profile} class may also be used to configure WebDriver based on a
- * pre-existing browser profile:
+ * The {@linkplain Profile} class may also be used to configure WebDriver based
+ * on a pre-existing browser profile:
  *
- *     var profile = new firefox.Profile(
+ *     let profile = new firefox.Profile(
  *         '/usr/local/home/bob/.mozilla/firefox/3fgog75h.testing');
- *     var options = new firefox.Options().setProfile(profile);
- *     var driver = new firefox.Driver(options);
+ *     let options = new firefox.Options().setProfile(profile);
  *
  * The FirefoxDriver will _never_ modify a pre-existing profile; instead it will
  * create a copy for it to modify. By extension, there are certain browser
@@ -56,21 +59,35 @@
  *
  * __Using a Custom Firefox Binary__
  *
- * On Windows and OSX, the FirefoxDriver will search for Firefox in its
+ * On Windows and MacOS, the FirefoxDriver will search for Firefox in its
  * default installation location:
  *
- * * Windows: C:\Program Files and C:\Program Files (x86).
- * * Mac OS X: /Applications/Firefox.app
+ * - Windows: C:\Program Files and C:\Program Files (x86).
+ * - MacOS: /Applications/Firefox.app
+ *
+ * For Linux, Firefox will always be located on the PATH: `$(where firefox)`.
  *
- * For Linux, Firefox will be located on the PATH: `$(where firefox)`.
+ * Several methods are provided for starting Firefox with a custom executable.
+ * First, on Windows and MacOS, you may configure WebDriver to check the default
+ * install location for a non-release channel. If the requested channel cannot
+ * be found in its default location, WebDriver will fallback to searching your
+ * PATH. _Note:_ on Linux, Firefox is _always_ located on your path, regardless
+ * of the requested channel.
+ *
+ *     const {Builder} = require('selenium-webdriver');
+ *     const firefox = require('selenium-webdriver/firefox');
+ *
+ *     let options = new firefox.Options().setBinary(firefox.Channel.NIGHTLY);
+ *     let driver = new Builder()
+ *         .forBrowser('firefox')
+ *         .setFirefoxOptions(options)
+ *         .build();
  *
- * You can configure WebDriver to start use a custom Firefox installation with
- * the {@link Binary} class:
+ * On all platforms, you may configrue WebDriver to use a Firefox specific
+ * executable:
  *
- *     var firefox = require('selenium-webdriver/firefox');
- *     var binary = new firefox.Binary('/my/firefox/install/dir/firefox-bin');
- *     var options = new firefox.Options().setBinary(binary);
- *     var driver = new firefox.Driver(options);
+ *     let options = new firefox.Options()
+ *         .setBinary('/my/firefox/install/dir/firefox-bin');
  *
  * __Remote Testing__
  *
@@ -84,11 +101,14 @@
  * binaries are never copied to remote machines and must be referenced by
  * installation path.
  *
- *     var options = new firefox.Options()
+ *     const {Builder} = require('selenium-webdriver');
+ *     const firefox = require('selenium-webdriver/firefox');
+ *
+ *     let options = new firefox.Options()
  *         .setProfile('/profile/path/on/remote/host')
  *         .setBinary('/install/dir/on/remote/host/firefox-bin');
  *
- *     var driver = new (require('selenium-webdriver')).Builder()
+ *     let driver = new Builder()
  *         .forBrowser('firefox')
  *         .usingServer('http://127.0.0.1:4444/wd/hub')
  *         .setFirefoxOptions(options)
@@ -99,8 +119,7 @@
  * To test versions of Firefox prior to Firefox 47, you must disable the use of
  * the geckodriver using the {@link Options} class.
  *
- *     var options = new firefox.Options().useGeckoDriver(false);
- *     var driver = new firefox.Driver(options);
+ *     let options = new firefox.Options().useGeckoDriver(false);
  *
  * Alternatively, you may disable the geckodriver at runtime by setting the
  * environment variable `SELENIUM_MARIONETTE=false`.
@@ -113,7 +132,7 @@
 
 const url = require('url');
 
-const Binary = require('./binary').Binary,
+const {Binary, Channel} = require('./binary'),
     Profile = require('./profile').Profile,
     decodeProfile = require('./profile').decode,
     http = require('../http'),
@@ -196,16 +215,24 @@ class Options {
   }
 
   /**
-   * Sets the binary to use. The binary may be specified as the path to a Firefox
-   * executable, or as a {@link Binary} object.
+   * Sets the binary to use. The binary may be specified as the path to a
+   * Firefox executable, a specific {@link Channel}, or as a {@link Binary}
+   * object.
    *
-   * @param {(string|!Binary)} binary The binary to use.
+   * @param {(string|!Binary|!Channel)} binary The binary to use.
    * @return {!Options} A self reference.
+   * @throws {TypeError} If `binary` is an invalid type.
    */
   setBinary(binary) {
-    if (typeof binary === 'string') {
+    if (typeof binary === 'string' || binary instanceof Channel) {
       binary = new Binary(binary);
     }
+
+    if (!(binary instanceof Binary)) {
+      throw TypeError(
+          'binary must be a string path, Channel, or Binary object');
+    }
+
     this.binary_ = binary;
     return this;
   }
@@ -687,6 +714,7 @@ class Driver extends webdriver.WebDriver {
 
 
 exports.Binary = Binary;
+exports.Channel = Channel;
 exports.Context = Context;
 exports.Driver = Driver;
 exports.Options = Options;