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/sys_random_test.cpp b/tests/sys_random_test.cpp
index 78cbf4a..2e2665b 100644
--- a/tests/sys_random_test.cpp
+++ b/tests/sys_random_test.cpp
@@ -43,7 +43,7 @@
   ASSERT_EQ(0, getentropy(buf2, sizeof(buf2)));
   ASSERT_TRUE(memcmp(buf1, buf2, sizeof(buf1)) != 0);
 #else
-  GTEST_LOG_(INFO) << "This test requires a C library with <sys/random.h>.\n";
+  GTEST_SKIP() << "<sys/random.h> not available";
 #endif
 }
 
@@ -53,7 +53,7 @@
   ASSERT_EQ(-1, getentropy(nullptr, 1));
   ASSERT_EQ(EFAULT, errno);
 #else
-  GTEST_LOG_(INFO) << "This test requires a C library with <sys/random.h>.\n";
+  GTEST_SKIP() << "<sys/random.h> not available";
 #endif
 }
 
@@ -66,7 +66,7 @@
   ASSERT_EQ(-1, getentropy(buf, sizeof(buf)));
   ASSERT_EQ(EIO, errno);
 #else
-  GTEST_LOG_(INFO) << "This test requires a C library with <sys/random.h>.\n";
+  GTEST_SKIP() << "<sys/random.h> not available";
 #endif
 }
 
@@ -79,7 +79,7 @@
   ASSERT_EQ(64, getrandom(buf2, sizeof(buf2), 0));
   ASSERT_TRUE(memcmp(buf1, buf2, sizeof(buf1)) != 0);
 #else
-  GTEST_LOG_(INFO) << "This test requires a C library with <sys/random.h>.\n";
+  GTEST_SKIP() << "<sys/random.h> not available";
 #endif
 }
 
@@ -89,7 +89,7 @@
   ASSERT_EQ(-1, getrandom(nullptr, 256, 0));
   ASSERT_EQ(EFAULT, errno);
 #else
-  GTEST_LOG_(INFO) << "This test requires a C library with <sys/random.h>.\n";
+  GTEST_SKIP() << "<sys/random.h> not available";
 #endif
 }
 
@@ -100,6 +100,6 @@
   ASSERT_EQ(-1, getrandom(buf, sizeof(buf), ~0));
   ASSERT_EQ(EINVAL, errno);
 #else
-  GTEST_LOG_(INFO) << "This test requires a C library with <sys/random.h>.\n";
+  GTEST_SKIP() << "<sys/random.h> not available";
 #endif
 }