Update to latest trace-viewer (a7f1c1b3)

Includes rewrite of prefix.html to switch from TraceViewer
to timeline-view, and account for new location of the
vulcanizer.

Cherry-pick of ced05db70069f9d84c4b0dd9b3b26b94e3482336 from AOSP

Change-Id: I07285c64bde7d4bfe414c9e93b097435e118a069
2697 files changed