android: Fix evaluateJavaScriptForTests thread

WebContents methods needs to be called on the UI thread

Change-Id: Id297470786ca85a3a02b9514fc3c957368dbfb09
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1502032
Commit-Queue: Avi Drissman <avi@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#637722}
1 file changed