Remove default ChromeDriver port in arg parse

If null and required, Android driver will pick a random available one

lib/parser.js

@@ -236,12 +236,12 @@ const args = [
   }],
 
   [['--chromedriver-port'], {
-    defaultValue: 9515,
+    defaultValue: null,
     dest: 'chromeDriverPort',
     required: false,
     type: 'int',
     example: '9515',
-    help: 'Port upon which ChromeDriver will run',
+    help: 'Port upon which ChromeDriver will run. If not given, Android driver will pick a random available port.',
   }],
 
   [['--chromedriver-executable'], {

package.json

@@ -35,7 +35,7 @@
     "doc": "./docs"
   },
   "dependencies": {
-    "appium-android-driver": "^1.10.12",
+    "appium-android-driver": "^1.10.19",
     "appium-base-driver": "^2.0.8",
     "appium-fake-driver": "^0.1.10",
     "appium-ios-driver": "^1.12.2",