AU: delta compress the kernel partition

src/platform/update_engine/test_utils.h

Index: src/platform/update_engine/test_utils.h
diff --git a/src/platform/update_engine/test_utils.h b/src/platform/update_engine/test_utils.h
index 2a87f49ddbc70caf967d9fef7dc0dd2e67a9b73b..4bc107e03e23ed41d50fdbb403e130e756a52281 100644
--- a/src/platform/update_engine/test_utils.h
+++ b/src/platform/update_engine/test_utils.h
@@ -21,10 +21,6 @@ namespace chromeos_update_engine {
 bool WriteFileVector(const std::string& path, const std::vector<char>& data);
 bool WriteFileString(const std::string& path, const std::string& data);
 
-// Returns the size of the file at path. If the file doesn't exist or some
-// error occurrs, -1 is returned.
-off_t FileSize(const std::string& path);
-
 // Reads a symlink from disk. Returns empty string on failure.
 std::string Readlink(const std::string& path);