Setting the property to false prevents the key from being installed.
Useful for testing keys.
Bug: 122042717
Test: add 'installable: false' to the apex_key
'com.android.apex.test_package.key'. mma under
/system/apex/apexd/apexd_testdata. The key is not found under
out/target/product/..../system/etc/security/apex
Change-Id: Ibf70e4e8ea5e73432d06b1c4050df531eaafc85e
A new module type 'apex_key' is defined to specify public and private
key pair for APEXs. An APEX can refer to the module via the property
'key'. When building the APEX, the private key from the key module is
used to sign it. In addition, the public key from the key module is
automatically installed to /system/etc/security/apex.
Bug: 115721587
Test: m apex.test; m
/apex/com.android.example.apex@1 exists
Change-Id: I82666db095bd7a09f6c1b9cbea2db57ebc076cbf
