Convert URI scheme to lower case before checking if it is a file.

This fixes an edge case where a "File://" style URI could be passed in
but not pass this check, even though the underlying framework recognizes
this as a legitimate file.

Bug: 197328178
Test: See repro steps on http://b/197328178, was no longer able to
repro.

Change-Id: Id837744a79d1aca91b41d24207dc9b98f2b5b5e9
(cherry picked from commit 9607c95e7164e7856c45fd9d07eea9b09f9db681)
1 file changed