[Java] Add a test to verify that typedefs in types.hal does not mistakenly

generate a makefile rule.

Bug: 31678014
Test: regenerate makefiles using hidl-gen.
Change-Id: I72ceaedd33288269b74e2aa233043c741994cd1a
diff --git a/tests/baz/1.0/Android.mk b/tests/baz/1.0/Android.mk
index 165237f..a0b36b0 100644
--- a/tests/baz/1.0/Android.mk
+++ b/tests/baz/1.0/Android.mk
@@ -9,6 +9,23 @@
 HIDL := $(HOST_OUT_EXECUTABLES)/hidl-gen$(HOST_EXECUTABLE_SUFFIX)
 
 #
+# Build types.hal
+#
+GEN := $(intermediates)/android/hardware/tests/baz/1.0/types.cpp
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+    $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+    -Lc++ -randroid.hardware:hardware/interfaces \
+    android.hardware.tests.baz@1.0::types
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
 # Build IBase.hal
 #
 GEN := $(intermediates)/android/hardware/tests/baz/1.0/BaseAll.cpp