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/string_test.cpp b/tests/string_test.cpp
index b27ca87..335d33b 100644
--- a/tests/string_test.cpp
+++ b/tests/string_test.cpp
@@ -85,7 +85,7 @@
 
   ASSERT_STREQ("Unknown error 1001", strerror1001);
 #else // __BIONIC__
-  GTEST_LOG_(INFO) << "Skipping test, requires a thread safe strerror.";
+  GTEST_SKIP() << "thread-safe strerror not available";
 #endif // __BIONIC__
 }
 
@@ -578,7 +578,7 @@
     }
   }
 #else
-  GTEST_LOG_(INFO) << "Skipping test, strlcat not supported on this platform.";
+  GTEST_SKIP() << "strlcat not available";
 #endif
 }
 
@@ -610,7 +610,7 @@
                  (memcmp(state.ptr2, state.ptr + state.MAX_LEN, state.MAX_LEN) != 0));
   }
 #else
-  GTEST_LOG_(INFO) << "Skipping test, strlcpy not supported on this platform.";
+  GTEST_SKIP() << "strlcpy not available";
 #endif
 }
 
@@ -1139,7 +1139,7 @@
 #if defined(STRLCPY_SUPPORTED)
   RunSrcDstBufferAlignTest(LARGE, DoStrlcpyTest);
 #else
-  GTEST_LOG_(INFO) << "Skipping test, strlcpy not supported on this platform.";
+  GTEST_SKIP() << "strlcpy not available";
 #endif
 }
 
@@ -1147,7 +1147,7 @@
 #if defined(STRLCPY_SUPPORTED)
   RunSrcDstBufferOverreadTest(DoStrlcpyTest);
 #else
-  GTEST_LOG_(INFO) << "Skipping test, strlcpy not supported on this platform.";
+  GTEST_SKIP() << "strlcpy not available";
 #endif
 }
 
@@ -1275,7 +1275,7 @@
 #if defined(STRLCAT_SUPPORTED)
   RunSrcDstBufferAlignTest(MEDIUM, DoStrlcatTest, LargeSetIncrement);
 #else
-  GTEST_LOG_(INFO) << "Skipping test, strlcat not supported on this platform.";
+  GTEST_SKIP() << "strlcat not available";
 #endif
 }
 
@@ -1283,7 +1283,7 @@
 #if defined(STRLCAT_SUPPORTED)
   RunSrcDstBufferOverreadTest(DoStrlcatTest);
 #else
-  GTEST_LOG_(INFO) << "Skipping test, strlcat not supported on this platform.";
+  GTEST_SKIP() << "strlcat not available";
 #endif
 }