Fix linking in of libraires by test targets multiple times.

The fix ensures that the libraries we link to for targets are unique.


[SVN r19096]

tools/build

@@ -1 +1 @@
-Subproject commit 94bec3a1e068d6508ba205b705cfc9fd058aec57
+Subproject commit b03e54c968adcef5922f5f24624ebe1d2f4044bf