Store ndkKnownLibs in the config

Storing ndkKnownLibs prevents multiple tests from running in parallel
as one may be writing to the list while another is reading from it.
Store it in the config so each test has its own copy.

Test: go test -race ./apex
Change-Id: Iba57c9494012c9e0ae9e5ffaa63b9b2bd2c77492
diff --git a/java/app.go b/java/app.go
index 17de8b9..3446739 100755
--- a/java/app.go
+++ b/java/app.go
@@ -890,7 +890,7 @@
 
 		if IsJniDepTag(tag) || cc.IsSharedDepTag(tag) {
 			if dep, ok := module.(*cc.Module); ok {
-				if dep.IsNdk() || dep.IsStubs() {
+				if dep.IsNdk(ctx.Config()) || dep.IsStubs() {
 					return false
 				}