Make tracing based Timeline stop after reloading inspected page

This change fixes the following problem:
1. Run browser with remote debugging enabled (--remote-debugging-port=9222)
2. Open remote debugging front-end in the same browser (localhost:9222)
3. Inspect that front-end using built-in DevTools.
4. Go to Timeline and press Ctrl+R

Result:
Timeline recording starts automatically and never stops after reload.

With this patch:
It will stop recoding after reload.

BUG=None

Review URL: https://codereview.chromium.org/409073003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@284706 0039d316-1c4b-4281-b951-d872f2087c98
2 files changed