Add support for multiple flavors of the NDK gtest.

Since gtest depends on the STL, we need one version for each STL.

Bug: http://b/27801981
Change-Id: Id1a5571b043e2513d0184a9ab45a473dd545da84
diff --git a/core/target_test_internal.mk b/core/target_test_internal.mk
index 030ca40..9e25674 100644
--- a/core/target_test_internal.mk
+++ b/core/target_test_internal.mk
@@ -5,9 +5,20 @@
 LOCAL_CFLAGS += -DGTEST_OS_LINUX_ANDROID -DGTEST_HAS_STD_STRING
 
 ifndef LOCAL_SDK_VERSION
-LOCAL_STATIC_LIBRARIES += libgtest_main libgtest
+    LOCAL_STATIC_LIBRARIES += libgtest_main libgtest
 else
-LOCAL_STATIC_LIBRARIES += libgtest_main_ndk libgtest_ndk
+    ifneq (,$(filter c++_%,$(LOCAL_NDK_STL_VARIANT)))
+        my_ndk_gtest_suffix := _libcxx
+    else ifneq ($(filter stlport_,$(LOCAL_NDK_STL_VARIANT)),)
+        my_ndk_gtest_suffix :=
+    else ifneq ($(filter gnustl_,$(LOCAL_NDK_STL_VARIANT)),)
+        my_ndk_gtest_suffix := _gnustl
+    else # system STL, use stlport
+        my_ndk_gtest_suffix :=
+    endif
+    LOCAL_STATIC_LIBRARIES += \
+        libgtest_main_ndk$(my_ndk_gtest_suffix) \
+        libgtest_ndk$(my_ndk_gtest_suffix)
 endif
 
 ifdef LOCAL_MODULE_PATH