[chromedriver] Disable testChromeDriverSendLargeData on webview_shell

This was accidentally enabled in crrev.com/680463002.

BUG=chromedriver:913
TBR=stgao@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/678703002

Cr-Commit-Position: refs/heads/master@{#301120}