Auto merge of #21242 - servo:android-wpt, r=jdm

Run a couple WPT tests on Android on CI

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etc/ci/buildbot_steps.yml

@@ -167,6 +167,8 @@ android-x86:
   - ./etc/ci/bootstrap-android-and-accept-licences.sh
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach build --target i686-linux-android --release
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach test-android-startup --release
+  - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach test-wpt-android --release /_mozilla/mozilla/DOMParser.html
+  - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach test-wpt-android --release /_mozilla/mozilla/webgl/context_creation_error.html
   - bash ./etc/ci/lockfile_changed.sh
 
 android-nightly:

etc/run_in_headless_android_emulator.py

@@ -54,6 +54,7 @@ def main(avd_name, apk_path, *args):
         check_call(adb + ["install", "-r", apk_path])
         args = list(args)
         write_user_stylesheets(adb, args)
+        write_hosts_file(adb)
         write_args(adb, args)
 
         check_call(adb + ["shell", "am start com.mozilla.servo/com.mozilla.servo.MainActivity"],
@@ -143,6 +144,15 @@ def write_user_stylesheets(adb, args):
         check_call(adb + ["push", path, remote_path], stdout=sys.stderr)
 
 
+def write_hosts_file(adb):
+    hosts_file = os.environ.get("HOST_FILE")
+    if hosts_file:
+        data_dir = "/sdcard/Android/data/com.mozilla.servo/files"
+        check_call(adb + ["shell", "mkdir -p %s" % data_dir])
+        remote_path = data_dir + "/android_hosts"
+        check_call(adb + ["push", hosts_file, remote_path], stdout=sys.stderr)
+
+
 def forward_webdriver(adb, args):
     webdriver_port = extract_arg("--webdriver", args)
     if webdriver_port is not None: