Issue 5500079: Supply custom setup element in EngineDesc.

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J / K :	jump to next file with a comment after / before current file
	Side-by-side diff
i :	toggle intra-line diffs
e :	expand all comments
c :	collapse all comments
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n / p :	next / previous diff chunk or comment
N / P :	next / previous comment
<Up> / <Down> :	next / previous line
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d :	mark current comment as done

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j / k :	jump to patch after / before current patch
o / <Enter> :	open current patch in side-by-side view
i :	open current patch in unified diff view

	Issue List
j / k :	jump to issue after / before current issue
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<Ctrl> + s or <Ctrl> + Enter :	save comment
<Esc> :	cancel edit