Editor panes are not auto resized when focused

[oujiafan]

• VSCode Version: 1.25.1
• OS Version: macOS 10.13.4

Steps to Reproduce:

1. Drag a file from main editor pane to right side.
2. Click the right pane to focus.
3. In previous version of VSCode, the right editor pane should automatically resize and become major editor pane. But in current version it doesn't.

Does this issue occur when all extensions are disabled?: Yes

[vscodebot]

(Experimental duplicate detection)
Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• Allow for empty editor panes (#2755)
• Restore "snap to minimize/maximize" feature with grid editor layout (#51614)
• Split Editor Pane's Initial State Should Be Empty (#30168)
• Allow to Collapse Window Pane (#44318)
• Allow maximizing/reverting the terminal pane (#47661)

[V-ed]

Duplicate of #51614

[oujiafan]

Confirmed dup.