Fixed bug when clearing file, winscope could not allow up/down arrows.

Test: run yarn dev. First launch a file on winscope, clear, then launch a
second, different file. Now, the up/down arrows will be able to function again.
Change-Id: I4140a1a8f8e1c4d9d2cef054456003aec5661412
Merged-In: I4140a1a8f8e1c4d9d2cef054456003aec5661412
1 file changed