[chromedriver] Disable testEmulateNetworkConditions on WebView

BUG=
TBR=stgao@chromium.org

Review URL: https://codereview.chromium.org/1015463002

Cr-Commit-Position: refs/heads/master@{#320750}

chrome/test/chromedriver/test/run_py_tests.py

@@ -157,6 +157,7 @@ _ANDROID_NEGATIVE_FILTER['chromedriver_webview_shell'] = (
         'PerformanceLoggerTest.testPerformanceLogger',
         'ChromeDriverTest.testShadowDom*',
         # WebView doesn't support emulating network conditions.
+        'ChromeDriverTest.testEmulateNetworkConditions',
         'ChromeDriverTest.testEmulateNetworkConditionsOffline',
     ]
 )