[chromedriver] Fix broken test on Android.
[chromedriver] Fix broken test on Android.

Make sure ChromeDriverLogTest.testDisablingDriverLogsSuppressesChromeDriverLog
doesn't try to launch a desktop browser session when running on Android. The
logic in ChromeDriverBaseTest.CreateDriver() does the right thing for Android,
so use that instead of creating a driver directly.

Common code between tests in ChromeDriverLogTest still need to be factored out
into separate setUp and tearDown methods in a separate CL.

BUG=chromedriver:1266
TBR=stgao@chromium.org

Review URL: https://codereview.chromium.org/1672243002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#373967}

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