Warn if oat file does end with expected extension

(cherry picked from commit 272df23ebb17297b53a60906304a35bc56eebdd9)

Change-Id: If126ee29811546698f2a8f9bb62300c2a9391017
diff --git a/src/utils_test.cc b/src/utils_test.cc
index 3228bb6..3c93e4d 100644
--- a/src/utils_test.cc
+++ b/src/utils_test.cc
@@ -307,4 +307,18 @@
   EXPECT_EQ("foo:bar:baz", Join(strings, ':'));
 }
 
+TEST_F(UtilsTest, StartsWith) {
+  EXPECT_FALSE(StartsWith("foo", "bar"));
+  EXPECT_TRUE(StartsWith("foo", "foo"));
+  EXPECT_TRUE(StartsWith("food", "foo"));
+  EXPECT_FALSE(StartsWith("fo", "foo"));
+}
+
+TEST_F(UtilsTest, EndsWith) {
+  EXPECT_FALSE(EndsWith("foo", "bar"));
+  EXPECT_TRUE(EndsWith("foo", "foo"));
+  EXPECT_TRUE(EndsWith("foofoo", "foo"));
+  EXPECT_FALSE(EndsWith("oo", "foo"));
+}
+
 }  // namespace art