Update getopts

*Sigh* https://github.com/rust-lang-nursery/getopts/pull/53#issuecomment-415770100

tests/wpt/metadata/MANIFEST.json

@@ -642276,7 +642276,7 @@
    "support"
   ],
   "tools/wptrunner/wptrunner/browsers/servodriver.py": [
-   "6486a788b8c8fbf4fc52dd4368265571975cabb4",
+   "d788effc469bc2f582ba7ead65700e7a13c37c59",
    "support"
   ],
   "tools/wptrunner/wptrunner/browsers/webkit.py": [
@@ -642524,7 +642524,7 @@
    "support"
   ],
   "tools/wptrunner/wptrunner/webdriver_server.py": [
-   "9ecd009a7d8127ed793d4ef0aff19f6161bbd1ec",
+   "4ec415ce78bb89a82d5f098b1c4e8560e7ec39e4",
    "support"
   ],
   "tools/wptrunner/wptrunner/wptcommandline.py": [

tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/browsers/servodriver.py

@@ -106,7 +106,7 @@ class ServoWebDriverBrowser(Browser):
             self.binary,
             self.binary_args + [
                 "--hard-fail",
-                "--webdriver", str(self.webdriver_port),
+                "--webdriver=%s" % self.webdriver_port,
                 "about:blank",
             ],
             self.debug_info

tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/webdriver_server.py

@@ -197,7 +197,7 @@ class ServoDriverServer(WebDriverServer):
 
     def make_command(self):
         command = [self.binary,
-                   "--webdriver", str(self.port),
+                   "--webdriver=%s" % self.port,
                    "--hard-fail",
                    "--headless"] + self._args
         if self.binary_args: