Log viewer resets DataTable/Graph split when window is made wider

Making the log viewer window winder unnecessarily affects the position of the split between the graphing area (at the top) and the data table area (at the bottom).

Here is a picture of the window before:

And here it is a moment later after I have grabbed the right side and made it winder by a few pixels

Start by reproducing the resize in the log viewer and locating the log viewer's split-layout entry point; the issue names no files or tests. Done means widening the window no longer changes the existing vertical split between the graph and data table.

Written by the indexing model from the issue text.