bionic tests: use GTEST_SKIP.

Also be a bit more to the point in our messages, focusing on "why" not
"what".

Test: ran tests
Change-Id: I297806c7a102bd52602dcd2fcf7a2cd34aba3a11
diff --git a/tests/membarrier_test.cpp b/tests/membarrier_test.cpp
index 9e871c7..6f650e7 100644
--- a/tests/membarrier_test.cpp
+++ b/tests/membarrier_test.cpp
@@ -46,8 +46,7 @@
 
 TEST(membarrier, global_barrier) {
   if (!HasMembarrier(MEMBARRIER_CMD_GLOBAL)) {
-    GTEST_LOG_(INFO) << "MEMBARRIER_CMD_GLOBAL not supported, skipping test.";
-    return;
+    GTEST_SKIP() << "MEMBARRIER_CMD_GLOBAL not supported";
   }
   ASSERT_EQ(0, syscall(__NR_membarrier, MEMBARRIER_CMD_GLOBAL, 0));
 }
@@ -78,14 +77,10 @@
 static void TestRegisterAndBarrierCommands(int membarrier_cmd_register,
                                            int membarrier_cmd_barrier) {
   if (!HasMembarrier(membarrier_cmd_register)) {
-    GTEST_LOG_(INFO) << MembarrierCommandToName(membarrier_cmd_register)
-        << " not supported, skipping test.";
-    return;
+    GTEST_SKIP() << MembarrierCommandToName(membarrier_cmd_register) << " not supported";
   }
   if (!HasMembarrier(membarrier_cmd_barrier)) {
-    GTEST_LOG_(INFO) << MembarrierCommandToName(membarrier_cmd_barrier)
-        << " not supported, skipping test.";
-    return;
+    GTEST_SKIP() << MembarrierCommandToName(membarrier_cmd_barrier) << " not supported";
   }
 
   ScopedErrnoCleaner errno_cleaner;