[DevTools] Do not enable touch emulation when inspect mode is already engaged.

We already disable touch when togging inspect mode. But if it was enabled
before entering device mode, touch was enabled anyway.

BUG=586060

Review URL: https://codereview.chromium.org/1693493003

Cr-Commit-Position: refs/heads/master@{#375052}
2 files changed