Fix media_cas_proxy_sdk build issue.

Add example binary for testing building the SDK after 'git clone' from our repo.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=227583629

common/string_util.h

@@ -10,14 +10,14 @@
 #define COMMON_STRING_UTIL_H_
 
 #include <string>
-#include "util/status.h"
+#include "common/status.h"
 
 namespace widevine {
 namespace string_util {
 
 // Converts std::string representation of a bitset to its binary equivalent string.
 // For example, converts "01110100011001010111001101110100" to "test".
-util::Status BitsetStringToBinaryString(const std::string& bitset, std::string* output);
+Status BitsetStringToBinaryString(const std::string& bitset, std::string* output);
 
 }  // namespace string_util
 }  // namespace widevine