With clang 3.4 ASAN there is the problem that the smoketest fails if run
in "make check" while trying to start the JVM, in getJavaProps()
it forks a "java" process and that fails due to lack of memory.

Avoid that problem by running the extension test first, when there is
only one application loaded, so the process is using much less memory.

Change-Id: I7e8bdc6ceea65b212f376943c7814ad1cf28675d