Fix RUNTIME_TARGET_GTEST_MAKE_TARGETS

There are a few modules that are `test_per_src: false`, so the guess of
the module name does not work.

Bug: 126890843
Test: see fewer warnings about missing modules on internal master
Change-Id: Ib7d85b80b0629c1ddd17feb3b0477062bae6c179
diff --git a/build/Android.gtest.mk b/build/Android.gtest.mk
index 2a88d85..960a51e 100644
--- a/build/Android.gtest.mk
+++ b/build/Android.gtest.mk
@@ -609,9 +609,16 @@
 # Used outside the art project to get a list of the current tests
 RUNTIME_TARGET_GTEST_MAKE_TARGETS :=
 art_target_gtest_files := $(foreach m,$(ART_TEST_MODULES),$(ART_TEST_LIST_device_$(TARGET_ARCH)_$(m)))
+# If testdir == testfile, assume this is not a test_per_src module
 $(foreach file,$(art_target_gtest_files),\
-  $(eval RUNTIME_TARGET_GTEST_MAKE_TARGETS += $$(notdir $$(patsubst %/,%,$$(dir $$(file))))_$$(notdir $$(basename $$(file))))\
+  $(eval testdir := $$(notdir $$(patsubst %/,%,$$(dir $$(file)))))\
+  $(eval testfile := $$(notdir $$(basename $$(file))))\
+  $(if $(call streq,$(testdir),$(testfile)),,\
+    $(eval testfile := $(testdir)_$(testfile)))\
+  $(eval RUNTIME_TARGET_GTEST_MAKE_TARGETS += $(testfile))\
 )
+testdir :=
+testfile :=
 art_target_gtest_files :=
 
 # Define all the combinations of host/target and suffix such as: