docs: Fixed error in code sample.

The code sample didn't match the sample project. Also rewrote one
paragraph to clarify that you *create* a particular XML file (external
bug report said the file was missing from the sample project).

Also fixed formatting in a different line sample (overlong line
forced code box to scroll).

Doc is staged to:
http://asolovay.mtv:9098/training/contacts-provider/retrieve-names.html#NameMatch

bug: 15377898
Change-Id: I0898956255aa9174b12811e6f6ca826434b28c20