check build tests modules in eng and userdebug builds

To catch more build breakage, check build tests modules in eng and
userdebug builds.

Change-Id: Ic3b34dcd199e50e555c33eb686a501acef59a8c2
diff --git a/core/.main.mk.swp b/core/.main.mk.swp
new file mode 100644
index 0000000..a044e50
--- /dev/null
+++ b/core/.main.mk.swp
Binary files differ
diff --git a/core/main.mk b/core/main.mk
index 048d2c3..3b5a023 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -992,6 +992,10 @@
 target-native-tests : native-target-tests
 tests : host-tests target-tests
 
+# To catch more build breakage, check build tests modules in eng and userdebug builds.
+ifneq ($(filter eng userdebug,$(TARGET_BUILD_VARIANT)),)
+droidcore : target-tests host-tests
+endif
 
 .PHONY: lintall