If you still need to old behavior of searching for a library we use the new PublicSystemLibraries instead (used very sparingly).
Also updated conventions on importing Android libraries to use the newly introduced Android Architecture instead, which is always set to a valid architecuture (unlike Target.Architecture for the general case)
Lastly I updated some build.cs files that were doing filesystem enumeration or copying as they were being parsed, this is highly discouraged (partially because we cache filesystem operations but also it adds a cost to something we expect to be very fast). Any operations like this should be done as part of the build if they have to be done at all.
#rb none
[CL 7918851 by Joakim Lindqvist in Dev-Build branch]
