…without cache

When the value of --drilldowns[LABEL].columns[NAME].window.sort_keys
parameter is changed, Groonga returns result without using cache.

When the value of --drilldown_filter parameter is changed, Groonga
returns result without using cache.

…mns-window-sort-keys

test: add drilldowns[LABEL].columns[NAME].window.sort_keys without cache

Patch by Kentaro Hayashi. Thanks!!!

test: add drilldown_filter test case without cache

Patch by Kentaro Hayashi. Thanks!!!

…t error

This test case checks whether drilldowns[LABEL].filter with empty
records of dynamic columns (price_with_tax) in initial stage doesn't
cause an error.

…s-with-drilldowns-label-filter

test: add no hit dynamic columns with drilldowns[LABEL].filter without error

Patch by Kentaro Hayashi. Thanks!!!

When the value of --drilldowns[LABEL].columns[NAME].flags parameter is
changed, Groonga returns result without using cache.