Allow java_sdk_library in an APEX to have higher min_sdk_version.

Inidividual boot or system server jars may have higher min_sdk_version
than the contianing apex, since the runtime respects the values of
min/max_sdk_version; e.g. runtime would not load a boot jar with
higher min_sdk_version. This allows shipping new boot jars via apexes
that target older platforms.

Bug: 190818041
Test: presubmit
Change-Id: I08ec0b4463a17bc8265b948fe09da55eb4e52ac3