AU: Many minor cleanup changes

src/platform/update_engine/utils_unittest.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <errno.h>
 #include <string>
 #include <vector>
 #include <gtest/gtest.h>
@@ skipping 107 matching lines @@
 }
 
 TEST(UtilsTest, TempFilenameTest) {
   const string original = "/foo.XXXXXX";
   const string result = utils::TempFilename(original);
   EXPECT_EQ(original.size(), result.size());
   EXPECT_TRUE(utils::StringHasPrefix(result, "/foo."));
   EXPECT_FALSE(utils::StringHasSuffix(result, "XXXXXX"));
 }
 
+TEST(UtilsTest, RootDeviceTest) {
+  EXPECT_EQ("/dev/sda", utils::RootDevice("/dev/sda3"));
+  EXPECT_EQ("/dev/mmc0", utils::RootDevice("/dev/mmc0p3"));
+}
+
+TEST(UtilsTest, PartitionNumberTest) {
+  EXPECT_EQ("3", utils::PartitionNumber("/dev/sda3"));
+  EXPECT_EQ("3", utils::PartitionNumber("/dev/mmc0p3"));
+}
+
 }  // namespace chromeos_update_engine