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/sha_util_test.cc

@@ -48,6 +48,18 @@ TEST(ShaUtilTest, Sha256) {
             Sha256_Hash("random data"));
 }
 
+TEST(ShaUtilTest, Sha512) {
+  const uint8_t kExpected[] = {
+      0x8f, 0x49, 0x93, 0x1f, 0x4d, 0x4a, 0x67, 0x6f, 0x9a, 0x7e, 0x62,
+      0x60, 0xea, 0xe1, 0x54, 0xfe, 0xe2, 0x75, 0x3c, 0xec, 0x3b, 0xb2,
+      0x2e, 0xd7, 0x51, 0xcc, 0x39, 0xf9, 0x89, 0x69, 0xad, 0xd0, 0x14,
+      0xaa, 0xbe, 0x40, 0xce, 0xe3, 0xab, 0xef, 0x10, 0x2f, 0x24, 0x0e,
+      0xd8, 0x26, 0x7b, 0xb5, 0x7d, 0x86, 0xce, 0xbd, 0xd7, 0x32, 0x86,
+      0x3a, 0x5e, 0x9e, 0x8d, 0x23, 0x77, 0x10, 0x80, 0x0c};
+  EXPECT_EQ(std::string(kExpected, kExpected + sizeof(kExpected)),
+            Sha512_Hash("random data"));
+}
+
 TEST(ShaUtilTest, GenerateSha1Uuid) {
   std::string name_space =
       absl::HexStringToBytes("4d20ad7dd95bc4b250fae56fb143e774");