AU: Include a bit flag (bit 31) in error codes to indicate non-normal boot mode.

BUG=chromium-os:10320
TEST=unit test, tested on device in normal and dev mode

Change-Id: I67d695bc167a4cc1a638711f047e2b86f8eaa8f1

Review URL: http://codereview.chromium.org/6098008
diff --git a/utils_unittest.cc b/utils_unittest.cc
index 185ab9a..0fda08f 100644
--- a/utils_unittest.cc
+++ b/utils_unittest.cc
@@ -29,6 +29,11 @@
   EXPECT_TRUE(utils::IsOfficialBuild());
 }
 
+TEST(UtilsTest, IsNormalBootMode) {
+  // Pretty lame test...
+  EXPECT_FALSE(utils::IsNormalBootMode());
+}
+
 TEST(UtilsTest, NormalizePathTest) {
   EXPECT_EQ("", utils::NormalizePath("", false));
   EXPECT_EQ("", utils::NormalizePath("", true));