matrix-js-sdk

c700d8da - Add utility to check for non migrated legacy db (#4055)

Add utility to check for non migrated legacy db (#4055) * Add utility to check for non migrated legacy db * code review changes * add unit tests for existsAndIsNotMigrated * ensure indexeddb is clean for each state (cherry picked from commit f94dbdec0fd8fa2043f04a06bdeb9a02665841c9)