Dataset/Gene/Pattern selectors - Clear search results if text input field is cleared

[adkinsrs]

If I type in a keyword for a dataset, for example, to filter datasets, the filtering correctly happens. But if I backspace or clear out the input box, the filtered datasets remain. I would expect to see all datasets in whatever view I'm in, or see no datasets at all if I have not selected a view if the input box has been cleared.

Assigning @jorvis for his selectors, and myself for the pattern one.

[jorvis]

Added code to handle the gene and dataset search parts, so removing myself from the assignment list.