extensions: tabs: set tab id to -1 for app/devtools windows
Before making app & devtools windows visible through chrome.windows.*
we want to make sure the tab id of the devtools is stripped from the
tab object returned to javascript so devtools cannot be manipulated
through the chrome.tabs.* API.
BUG=
394341
Committed:
https://crrev.com/d2315f72405e4776861fa79919a0051538660656
Cr-Commit-Position: refs/heads/master@{#339647}