Require NodeJS v8+ and NPM v5+

This updates our build requirements to NodeJS v8+ and NPM v5+, both
released in 2017.

This also clarifies our support for Python 3 (not well-documented
before) to the version we are using on Debian, v3.5.

Requiring NodeJS v8+ means our node tools (like our extern generator)
no longer need shims for compatibility.  This allows us to drop the
"es6-shim" and "array-includes" modules.

In NPM v5+, the "prepublish" script has been deprecated, and replaced
with "prepublishOnly" (which is what we want) and "prepare" (the old
behavior we had to work around).  This allows us to drop the
"in-publish" module.

Change-Id: Ied189c76a58fe981c12d41155b834f2d6ea73bbd

build/generateExterns.js

@@ -48,14 +48,6 @@ const fs = require('fs');
 // The annotations we will consider "exporting" a symbol.
 const EXPORT_REGEX = /@(?:export|exportInterface|expose)\b/;
 
-// Install ES6/ES7 polyfills for old versions of nodejs.
-if (!global.Set) {
-  require('es6-shim');
-}
-if (!Array.prototype.includes) {
-  require('array-includes').shim();
-}
-
 
 /**
  * Topological sort of general objects using a DFS approach.

build/install-linux-prereqs.sh

@@ -56,11 +56,11 @@ sudo apt -y update
 sudo apt -y install git python2.7 default-jre-headless apache2
 
 # NodeJS in Ubuntu and Debian is often out of date, so we may need to grab a
-# newer version.  We require v6+.
+# newer version.  We require v8+.
 
-if node --version 2>/dev/null | grep -q 'v\([6-9]\|1[0-9]\)'; then
+if node --version 2>/dev/null | grep -q 'v\([89]\|1[0-9]\)'; then
   echo "*****" 1>&2
-  echo "NodeJS v6+ detected.  No update needed." 1>&2
+  echo "NodeJS v8+ detected.  No update needed." 1>&2
   echo "*****" 1>&2
 else
   if node --version &>/dev/null; then
@@ -99,7 +99,7 @@ else
       fi
     else
       echo "*****" 1>&2
-      echo "You will need to upgrade NodeJS yourself to v6+." 1>&2
+      echo "You will need to upgrade NodeJS yourself to v8+." 1>&2
       echo "*****" 1>&2
       exit 1
     fi

build/shakaBuildHelpers.py

@@ -286,7 +286,7 @@ def update_node_modules():
   # Check the version of npm.
   version = execute_get_output([cmd, '-v']).decode('utf8')
 
-  if _parse_version(version) < _parse_version('1.3.12'):
+  if _parse_version(version) < _parse_version('5.0.0'):
     logging.error('npm version is too old, please upgrade.  e.g.:')
     logging.error('  npm install -g npm')
     return False
@@ -295,12 +295,9 @@ def update_node_modules():
   # Actually change directories instead of using npm --prefix.
   # See npm/npm#17027 and google/shaka-player#776 for more details.
   with InDir(base):
-    if _parse_version(version) >= _parse_version('5.0.0'):
-      # npm update seems to be the wrong thing in npm v5, so use install.
-      # See google/shaka-player#854 for more details.
-      execute_get_output([cmd, 'install'])
-    else:
-      execute_get_output([cmd, 'update'])
+    # npm update seems to be the wrong thing in npm v5, so use install.
+    # See google/shaka-player#854 for more details.
+    execute_get_output([cmd, 'install'])
 
   # Update the timestamp of the file that tracks when we last updated.
   open(_node_modules_last_update_path(), 'w').close()

docs/tutorials/welcome.md

@@ -28,9 +28,9 @@ externs have been generated.
 You can build Shaka on Linux, Windows, or Mac.
 To get the sources and compile the library, you will need:
   * {@link https://git-scm.com/downloads Git v1.9+}
-  * {@link https://www.python.org/downloads/ Python v2.7}
+  * {@link https://www.python.org/downloads/ Python v2.7 or v3.5+}
   * {@link https://java.com/en/download/ Java Runtime Environment v8+}
-  * {@link https://nodejs.org/en/download/ NodeJS v6+}
+  * {@link https://nodejs.org/en/download/ NodeJS v8+}
   * A local web server, such as {@link https://httpd.apache.org/ Apache}
     * _NOTE: A local web server is required because browsers place restrictions
       on applications from file:/// URLs._

package.json

@@ -11,20 +11,17 @@
     }
   ],
   "devDependencies": {
-    "array-includes": "^3.0.3",
     "awesomplete": "^1.1.4",
     "babel-core": "^6.26.3",
     "babel-polyfill": "^6.26.0",
     "babel-preset-env": "^1.7.0",
     "cajon": "^0.4.4",
     "dialog-polyfill": "^0.5.0",
     "es6-promise-polyfill": "^1.2.0",
-    "es6-shim": "^0.35.5",
     "eslint": "^5.16.0",
     "eslint-config-google": "^0.13.0",
     "esprima": "^4.0.1",
     "htmlhint": "^0.11.0",
-    "in-publish": "^2.0.0",
     "jasmine-ajax": "^4.0.0",
     "jasmine-core": "^3.4.0",
     "jsdoc": "github:joeyparrish/jsdoc#45c271fa",
@@ -62,6 +59,6 @@
   },
   "license": "Apache-2.0",
   "scripts": {
-    "prepublish": "in-publish && python build/checkversion.py && python build/all.py --force || not-in-publish"
+    "prepublishOnly": "python build/checkversion.py && python build/all.py --force"
   }
 }