This CL fixes the Map Panel colors. The getColor
function of Edge class was always falling to the
default color unable to show correct colors in
the timeline panel.

Change-Id: Ide13b35703a656251222f512b2b9282f9f34cc04
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2297473Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Zeynep Cankara <zcankara@google.com>
Cr-Commit-Position: refs/heads/master@{#68859}