Fix warnings on 64-bit-only builds

These tests set `LOCAL_MODULE_TARGET_ARCH := arm x86` unless
TARGET_ENABLE_MEDIADRM_64 is true, so for 64-bit-only configurations
that don't set this, these tests are disabled.

Test: lunch armv8-eng; m nothing  -> see fewer warnings
Change-Id: I7ca0e8c382eb9930b8b1477ee8c9f1ea40c6888f

tests/Android.mk

@@ -1,12 +1,16 @@
-# Build rules for tests to be included in the google_tests.zip package
-# are discovered by having an Android.mk file located in vendor/<project>/tests/.
-
 LOCAL_PATH := $(call my-dir)
 include $(CLEAR_VARS)
 
 # Targets to be included in google_tests.zip
 # Referenced by vendor/google/build/tasks/google_tests.mk
 WIDEVINE_TEST_MAKE_TARGETS := \
+    CastSignAPITest \
+    MediaDrmAPITest \
+
+# These tests only exist if we're building a 32-bit architecture, or TARGET_ENABLE_MEDIADRM_64
+# Importantly, they do not build on 64-bit only configurations that do not set TARGET_ENABLE_MEDIADRM_64
+ifneq ($(filter arm x86 true,$(TARGET_ARCH) $(TARGET_2ND_ARCH) $(TARGET_ENABLE_MEDIADRM_64)),)
+WIDEVINE_TEST_MAKE_TARGETS += \
     base64_test \
     buffer_reader_test \
     cdm_engine_test \
@@ -39,8 +43,8 @@ WIDEVINE_TEST_MAKE_TARGETS := \
     usage_table_header_unittest \
     value_metric_unittest \
     wv_cdm_metrics_test \
-    CastSignAPITest \
-    MediaDrmAPITest \
+
+endif
 
 # Call the makefiles for all our tests used in TradeFederation
 MODULAR_DRM_PATH := vendor/widevine/libwvdrmengine