Optimize DeviceTempFile() by combining logic into a single "adb shell"
Optimize DeviceTempFile() by combining logic into a single "adb shell"

Brings the no-op case of managed_install.py from 11s -> 9s for
chrome_modern_with_splits_managed when adb is forwarded over ssh.

BUG=520082

Review URL: https://codereview.chromium.org/1285263009

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#345115}

axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,Chilledheart/chromium,axinging/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,Chilledheart/chromium,axinging/chromium-crosswalk,Chilledheart/chromium,Chilledheart/chromium