Add source file provider for genrule/srcs, python libraries and rust libraries.

Ignore-AOSP-First: CPing test_spec rule to udc-mainline-prod to support migration of test targets. Cherry pick of:aosp/2786121

Change-Id: I2d7d4684a10c15aeecc27b8db800ab27a807d2e2
Merged-In: I2d7d4684a10c15aeecc27b8db800ab27a807d2e2
diff --git a/bpf/bpf.go b/bpf/bpf.go
index d135d5f..710d9cd 100644
--- a/bpf/bpf.go
+++ b/bpf/bpf.go
@@ -208,6 +208,7 @@
 		}
 
 	}
+	ctx.SetProvider(blueprint.SrcsFileProviderKey, blueprint.SrcsFileProviderData{SrcPaths: srcs.Strings()})
 }
 
 func (bpf *bpf) AndroidMk() android.AndroidMkData {