Allocate space using new StorageManager API.

Local storage devices might be willing to delete cached data to make
room for user-demanded data, such as copy operations.  So if the
source size is known, and the target supports allocation, then use
the new StorageManager APIs to pre-allocate that space.

Because this uses fallocate() internally it has multiple benefits,
including optimizing the on-disk layout, reducing fragmentation, and
preventing us from running out of space mid-copy.

Bug: 63057877
Test: bit DocumentsUITests:com.android.documentsui.services.CopyJobTest
Test: bit DocumentsUITests:com.android.documentsui.services.MoveJobTest
Change-Id: I8406e6e04294748993e8918351e37d70e5d02a45