Add "thermal" atrace category
Add "thermal" atrace category

Thermal has become more and more interesting when study
application/system behavior. This CL adds a new thermal
category.

Bug: 160818586
Test: perfetto -t 10s -b 16m -o /data/misc/perfetto-traces/trace thermal
Change-Id: I3b4476d1b4d11d355e08c57fab6f39c11a767e5b

google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto