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For displaying the vsync lines in the tool, we need the ideal vsync
timestamps. The tool was using the timestamps of the HW_VSYNC_0 events,
but this could be off and very jittery by several tenths of a
millisecond from the vsync event time just because those events are
written out by SurfaceFlinger when responding to the hardware composer
vsync callback.

The hardware composer vsync callback includes the actual vsync timestamp
as an argument, but this is not included in the existing event trace in
any way.

I went and added a new ARC_VSYNC event which includes the actual vsync
timestamp in the profile data, where it is stored in the string after
the event name. Reading this event and parsing out the actual timestamp
is much more accurate.

Switching the tracing tool to using the event means that the vsync lines
will be rendered with a consistent spacing, and represent the actual
vsync times now, instead of lagging behind by some variable amount.

Specifically this change

1) Modifies arc_tracing_event_matcher to allow for a prefix match, and
   not just an exact name match. Since the timestamp is part of the name
   string and is variable, a prefix match was required to match these
   events.
2) A unit test was added to cover the new matching behavior, and in
   implementing it I went ahead and added move constructors/assignment
   to ArcTracingEvent for convenience
3) Removes "disabled-by-default-android hal" from the trace options when
   the tool is used. It turned out this was including some events from
   HIDL ("HIDL::IComposerCallback::onVsync::passthrough"), which were
   emitted using atrace_begin/atrace_end, however which could actually
   execute on separate threads and break an assumption in the tracing
   tool that they were emitted by the same thread. Perhaps the Android
   HAL generator code could be adjusted to use atrace_async_begin and
   atrace_async_end instead, but since we do not seem to need the HAL
   events, it was easier to just disable their capture.
4) Switches the tracing model to look for the ARC_VSYNC events instead
   of the HW_VSYNC_0 events, including reading the timestamp out of the
   name string instead of using the misleading event timestamp.

BUG=b:132641796
TEST=unit_tests --gtest_filter=ArcTracingEventMatcherTest*
TEST=chrome://arc-graphics-tracing

Change-Id: I887a573c74035d783b918ca69c3dbb47fc1e5920
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1811936
Auto-Submit: Lloyd Pique <lpique@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Yury Khmel <khmel@chromium.org>
Commit-Queue: Lloyd Pique <lpique@chromium.org>
Cr-Commit-Position: refs/heads/master@{#702301}