[js] Another pass at the new actions API for #4564

The previous iteration heavily favored sequences where multiple devices acted
in each tick. This also made it too difficult for "simple" sequences like
"press SHIFT, move the mouse (0, 30), press LEFT, release LEFT, etc." This new
version goes back to favoring simple, synchronous sequences, but still allows
configuring async sequences.

The new input.Actions class API is largely compatible with
actions.LegacyActionSequence, however, the mouse methods have been renamed to
force a breakage since there is a change in parameters.

The new API still supports translating mouse+keyboard sequences to the legacy
protocol, but users have to explicitly request this when the sequence is first
created (translation is opt-in because it's not 100%; known issues are all
covered in the input.Actions class doc)

javascript/node/selenium-webdriver/CHANGES.md

@@ -120,6 +120,8 @@ mode.
        -  InvalidElementCoordinatesError
 *  Changes to `lib/webdriver.WebDriver`:
    -  Dropped support for "requiredCapabilities" from WebDriver.createSession
+   -  actions now returns the new `lib/input.Actions` class
+   -  removed touchActions
 *  Changes to `lib/webdriver.Alert`:
    -  Removed authenticateAs
 *  Changes to `lib/webdriver.Options` (`driver.manage()`):
@@ -153,14 +155,15 @@ mode.
 
 *  Revamped the actions API to conform with the WebDriver Spec:
    <https://www.w3.org/TR/webdriver/#actions>. For details, refer to the JS doc
-   on the `lib/webdriver.ActionSequence` class.
-
-   As of December, 2017, only Firefox supports this new API.
-   `ActionSequence#perform()` will attempt to translate mouse and keyboard
-   sequences to the legacy API. Alternatively, you may continue to use the
-   legacy API directly via the `lib/actions` module. __NOTE:__ The legacy API
-   is considered strongly deprecated and will be removed in a minor release once
-   Google's Chrome and Microsoft's Edge browsers support the new API.
+   on the `lib/input.Actions` class.
+
+   As of January, 2018, only Firefox natively supports this new API. You can
+   put the `Actions` class into "bridge mode" and it will attempt to translate
+   mouse and keyboard actions to the legacy API (see class docs). Alternatively,
+   you may continue to use the legacy API directly via the `lib/actions` module.
+   __NOTE:__ The legacy API is considered strongly deprecated and will be
+   removed in a minor release once Google's Chrome and Microsoft's Edge browsers
+   support the new API.
 
 *  All window manipulation commands are now supported.
 *  Added `driver.switchTo().parentFrame()`

javascript/node/selenium-webdriver/firefox.js

@@ -754,7 +754,7 @@ Channel.RELEASE = new Channel(
  * @see <https://www.mozilla.org/en-US/firefox/channel/desktop/#nightly>
  */
 Channel.NIGHTLY = new Channel(
-  '/Applications/FirefoxNightly.app/Contents/MacOS/firefox-bin',
+  '/Applications/Firefox Nightly.app/Contents/MacOS/firefox-bin',
   'Nightly\\firefox.exe');
 
 

javascript/node/selenium-webdriver/index.js

@@ -672,7 +672,6 @@ class Builder {
 // PUBLIC API
 
 
-exports.ActionSequence = webdriver.ActionSequence;
 exports.Browser = capabilities.Browser;
 exports.Builder = Builder;
 exports.Button = input.Button;