[DevTools] add DevTools DOM properties expanded ActionTaken to histogtams.xml
[DevTools] add DevTools DOM properties expanded ActionTaken to histogtams.xml

The CL adds name for DevTool DOM properties expanded action.

BUG=529913
R=pfeldman@chromium.org,paulirish@chromium.org,isherman@chromium.org

Review URL: https://codereview.chromium.org/1348293003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#363879}

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