[Chromedriver] Disable testShadowDomHover on HEAD

chrome/test/chromedriver/test/run_py_tests.py

Index: chrome/test/chromedriver/test/run_py_tests.py
diff --git a/chrome/test/chromedriver/test/run_py_tests.py b/chrome/test/chromedriver/test/run_py_tests.py
index 87ad41a41583ac2a708b5934b93f5a32042751e4..04bd89f7c7e81bea4c0b006b7f975fcd153b77c7 100755
--- a/chrome/test/chromedriver/test/run_py_tests.py
+++ b/chrome/test/chromedriver/test/run_py_tests.py
@@ -69,6 +69,8 @@ _VERSION_SPECIFIC_FILTER = {}
 _VERSION_SPECIFIC_FILTER['HEAD'] = [
     # https://code.google.com/p/chromedriver/issues/detail?id=992
     'ChromeDownloadDirTest.testDownloadDirectoryOverridesExistingPreferences',
+    # https://bugs.chromium.org/p/chromedriver/issues/detail?id=1503
+    'ChromeDriverTest.testShadowDomHover,
 ]
 
 _OS_SPECIFIC_FILTER = {}