Defer sitelinkview's switching to edit mode

When starting sitelinklistview's edit mode, instead of switching all
sitelinkviews to edit mode, only those sitelinkviews visible in the
viewport are switched to edit mode initially.

Bug: 73300
Change-Id: I9e46520f06b738002100639fe7dfdfcab07e1c80
Merge "Defer sitelinkview's switching to edit mode"