11b1577902
This change puts the file's access mode into the saved-state blob used by the file backup helpers. The tests have been updated for the new blob content format. What this change *doesn't* do is actually backup/restore the file mode. This change is a prerequisite for that, but mode preservation in backup/restore will require adding metadata to the backup data stream itself, so will be approached a bit more carefully. (Also fixed one outright bug in the test program: ReadEntityData() had been changed to return a ssize_t union of either a byte-count or a negative number indicating error, but the test program was still assuming that nonzero == error, and was spuriously failing.)
Android Utility Function Library If you need a feature that is native to Linux but not present on other platforms, construct a platform-dependent implementation that shares the Linux interface. That way the actual device runs as "light" as possible. If that isn't feasible, create a system-independent interface and hide the details. The ultimate goal is *not* to create a super-duper platform abstraction layer. The goal is to provide an optimized solution for Linux with reasonable implementations for other platforms.