Fix target gtest depenencies

The main ingredient was moving the include of Android.gest.mk earlier.
But then to keep host gtests dependencies working, their dependencies
were made to mirror how the target works, to hopefully avoid similar
issues in the future.

Change-Id: If7223b8a6f3a2fef449616494b14558e1752226d
diff --git a/build/Android.gtest.mk b/build/Android.gtest.mk
index b2313aa..3405e7e 100644
--- a/build/Android.gtest.mk
+++ b/build/Android.gtest.mk
@@ -102,7 +102,7 @@
 ART_TARGET_TEST_TARGETS += $$(art_gtest_target)
 else
 .PHONY: $$(art_gtest_target)
-$$(art_gtest_target): $$(art_gtest_exe) $(ART_HOST_TEST_DEPENDENCIES)
+$$(art_gtest_target): $$(art_gtest_exe) test-art-host-dependencies
 	$$<
 	@echo $$@ PASSED