Historically, the mapping implemented by MimeMap (formerly MimeUtils)
was largely untested and therefore differed between Android devices.
This CL topic makes CtsMimeMapTestCases a lot more opinionated by
checking that:
- MimeMap.getDefault() must respect all of the mappings supplied
in stock Android. This is enforced via CTS bundling a copy of:
- the {,android.,vendor.}mime.types data files
- DefaultMimeMapFactory (rewritten via jarjar to
android.content.type.cts.StockAndroidMimeMapFactory)
MimeMap.getDefault() is allowed to implement _additional_
mappings, but changed or removed mappings are not allowed.
- Public APIs android.webkit.MimeTypeMap and
URLConnection.getFileNameMap() must behave consistently with
MimeMap.getDefault() (in stock Android, those APIs are
implemented directly on top of MimeMap.getDefault()).
Test: atest CtsMimeMapTestCases
Test: atest CtsLibcoreTestCases:libcore.libcore.net.MimeMapTest
Test: The above atest runs pass on a device that contains an
additional mapping in vendor.mime.types that is not
present in CTS.
Test: Checked that on a device that changes a mapping in
android.mime.types, CtsLibcoreTestCases still passes
but CtsMimeMapTestCases fails.
Bug: 141842930
Bug: 139895945
Change-Id: I68e0e9c3ce53c1acf2a89f8b80519f4658c07217