Clean up issues causing webkit_lint to fail on windows.

A fuchsia-specific change landed that caused webkit_lint to
fail on windows when it tried to instantiate a Fuchsia configuration.

This CL fixes a number of small issues that caused that failure,
so that things will work correctly in the same situation in the future.

R=jbudorick@chromium.org, kmarshall@chromium.org
BUG=838703

Change-Id: I796ff68b5138e4c31d56121e9a7fa751ade48543
Reviewed-on: https://chromium-review.googlesource.com/1038570Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555240}

testing/buildbot/trybot_analyze_config.json

@@ -16,6 +16,7 @@
       "build/check_gn_headers.py",
       "build/check_gn_headers_whitelist.txt",
       "build/cipd/android/android.ensure",
+      "build/fuchsia/.*py",
       "build/get_landmines.py",
       "build/gyp_chromium",
       "build/mac_toolchain.py",

third_party/blink/tools/blinkpy/web_tests/port/fuchsia.py

@@ -53,7 +53,7 @@ qemu_target = None
 # Imports Fuchsia runner modules. This is done dynamically only when FuchsiaPort
 # is instantiated to avoid dependency on Fuchsia runner on other platforms.
 def _import_fuchsia_runner():
-    sys.path.append(os.path.join(get_chromium_src_dir(), 'build/fuchsia'))
+    sys.path.insert(0, os.path.join(get_chromium_src_dir(), 'build/fuchsia'))
 
     # pylint: disable=import-error
     # pylint: disable=invalid-name
@@ -191,7 +191,6 @@ class FuchsiaPort(base.Port):
     FALLBACK_PATHS = {'fuchsia': ['fuchsia'] + linux.LinuxPort.latest_platform_fallback_path()}
 
     def __init__(self, host, port_name, **kwargs):
-        _import_fuchsia_runner()
         super(FuchsiaPort, self).__init__(host, port_name, **kwargs)
 
         self._operating_system = 'fuchsia'
@@ -207,6 +206,7 @@ class FuchsiaPort(base.Port):
 
         self._target_host = self.get_option('fuchsia_target')
         self._zircon_logger = None
+        _import_fuchsia_runner()
 
     def _driver_class(self):
         return ChromiumFuchsiaDriver