Moved the cross-project parts of trace_event.h to trace_event_common.h
This means other projects can copy it unmodified and keep their implementation details in trace_event.h
trace_event_common.h also has some additional macros that were only found in the Blink copy of trace_event_.h previously.
R=dsinclair
BUG=
Review URL: https://codereview.chromium.org/1256263006
Cr-Commit-Position: refs/heads/master@{#341834}
CrOS-Libchrome-Original-Commit: e6e9521480c9c321f7e046da7a63ba9a0802f861
3 files changed