Use the location where FileDescriptorWatcher is created to track the libevent handlers
Currently the trace events are without the location information and it
is of less use without the location for heap profiler. The libevent
handlers are now annotated with the location where the watcher
controller is created for tracing and heap profiler.
This only handles the posix version of watcher events. Windows will be
fixed in different CL.
BUG=609912
Review-Url: https://codereview.chromium.org/2695593009
Cr-Commit-Position: refs/heads/master@{#451142}
CrOS-Libchrome-Original-Commit: 5dd4fb35920fffa84d53cb908b83668b2c7db1b8
7 files changed