Chrome Version: trunk @ r536327
OS: Win10

What steps will reproduce the problem?
(1) Grab a trace with flow events enabled

What is the expected result?
Arrows properly positioned.

What happens instead?
See attached trace and SS.

In this case, focus on "MajorGC" 5/6 and notice that the flow events for "TaskScheduler PostTask" events are not aligned with the actual events (scroll up and find them with proper horizontal alignment and shape in a random place at a bad vertical position).

This is not specific to this trace, I get this often. Somethings scrolling around makes the vertical offset budge (sometimes in the right place, but then it doesn't stick), it's fairly flaky..
 

Deleted: poor_flow_arrow_alignment_actual.png 99 KB

	poor_flow_arrow_alignment_actual.png 99 KB View Download

Deleted: poor_flow_arrow_alignment_expected.png 108 KB

	poor_flow_arrow_alignment_expected.png 108 KB View Download

Deleted: trace_flow_arrows_poorly_aligned.json.gz 3.8 MB

trace_flow_arrows_poorly_aligned.json.gz 3.8 MB Download