ART: Add three Timer functions

Add support for GetAvailableProcessors, GetTimerInfo and GetTime.
Add tests.

Bug: 31455788
Test: m test-art-host-run-test-926-timers
Change-Id: I9629654349787e27dee686284567b5de70e138f2
diff --git a/test/Android.bp b/test/Android.bp
index b0f0e5a..1ea1252 100644
--- a/test/Android.bp
+++ b/test/Android.bp
@@ -265,6 +265,7 @@
         "922-properties/properties.cc",
         "923-monitors/monitors.cc",
         "924-threads/threads.cc",
+        "927-timers/timers.cc",
     ],
     shared_libs: [
         "libbase",