Speed up search of assets in Asset Browser

[dkondrashkin]

LY-104815, LY-104815

Overal

• Disabled upward/downward propagation for all filters;
• Added 500 ms delay before FilterUpdatedSlotImmediate is called. This allows to make less filter updates when entering multiple symbols at once;
• Filter invalidation (invalidateFilter call) changed to model reset (begin/endResetModel calls). This is simply cheaper considering the amount of rows in the model;

In filterAcceptsRow method implementation:

• Added check for the entry's parent being a folder;
• Added cache of previously seen and accepted entries;
• Added recursive children lookup as a replacement for disabled filters propagation option.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[sourjon]

Hi @dkondrashkin ,

Thanks for the PR!