Revert of Add logspam to help diagnose flaky tests (patchset #2 id:20001 of https://codereview.chromium.org/485843002/)

Reason for revert:
No longer needed since AutomationApiTests have been running for some time without flaking.

Original issue's description:
> Add logspam to help diagnose flaky tests
>
> BUG=391279,385701,353039,379927,384673

TBR=kalman@chromium.org,aboxhall@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=391279,385701,353039,379927,384673

Review URL: https://codereview.chromium.org/561923002

Cr-Commit-Position: refs/heads/master@{#294236}

• chrome/browser/extensions/api/automation_internal/automation_util.cc[diff]
• chrome/renderer/resources/extensions/automation/automation_node.js[diff]
• chrome/renderer/resources/extensions/automation_custom_bindings.js[diff]
• chrome/test/data/extensions/api_test/automation/tests/tabs/common.js[diff]
• chrome/test/data/extensions/api_test/automation/tests/tabs_automation_boolean/common.js[diff]