hangyu 58eb0e8ae6
Update a11y for SliverAppBar (#144437)
1. Set cacheExtent for sliverAppBar so it's not dropped from the
semantics tree.
2. Update its toolbarOpacity in a11y mode to 1.0. When scrolling in a11y
mode and the focus is back to the sliverAppBar, the content should be
visible.
fixes: https://github.com/flutter/flutter/issues/143437


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2024-03-15 10:42:02 -07:00
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