Removed Common

Change-Id: I01ea8f07220375c2ad9bc0092281d4f27c642303
diff --git a/aos/util/wrapping_counter.cc b/aos/util/wrapping_counter.cc
new file mode 100644
index 0000000..f98d7e3
--- /dev/null
+++ b/aos/util/wrapping_counter.cc
@@ -0,0 +1,19 @@
+#include "aos/util/wrapping_counter.h"
+
+namespace aos {
+namespace util {
+
+WrappingCounter::WrappingCounter(int32_t initial_count)
+    : count_(initial_count), last_count_(0) {}
+
+int32_t WrappingCounter::Update(uint8_t current) {
+  if (last_count_ > current) {
+    count_ += 0x100;
+  }
+  count_ = (count_ & 0xffffff00) | current;
+  last_count_ = current;
+  return count_;
+}
+
+}  // namespace util
+}  // namespace aos