IsFileInUse should return false when the file doesn't exist.

chrome/installer/util/installer_state_unittest.cc

Index: chrome/installer/util/installer_state_unittest.cc
diff --git a/chrome/installer/util/installer_state_unittest.cc b/chrome/installer/util/installer_state_unittest.cc
index f62ea1bf216a8613d62017cce0e897ceb7a4a6f4..de1fcfccafc860fdb852afd80ad146bfa2577ecc 100644
--- a/chrome/installer/util/installer_state_unittest.cc
+++ b/chrome/installer/util/installer_state_unittest.cc
@@ -495,6 +495,17 @@ TEST_F(InstallerStateTest, IsFileInUse) {
   EXPECT_FALSE(MockInstallerState::IsFileInUse(temp_file));
 }
 
+TEST_F(InstallerStateTest, IsNonExistantFileInUse) {
+  base::ScopedTempDir temp_dir;
+  ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
+
+  FilePath temp_file;
+  ASSERT_TRUE(file_util::CreateTemporaryFileInDir(temp_dir.path(), &temp_file));
+  ASSERT_TRUE(file_util::Delete(temp_file, false));
+
+  // There's no file, so it had better not be in use.
+  EXPECT_FALSE(MockInstallerState::IsFileInUse(temp_file));
+}
 
 TEST_F(InstallerStateTest, RemoveOldVersionDirs) {
   MockInstallerState installer_state;