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

testing/BUILD

@@ -18,7 +18,6 @@ cc_library(
     ],
     deps = [
         "//external:gtest",
-        "//util:status",
     ],
 )
 

testing/gunit.h

@@ -11,9 +11,7 @@
 
 #include <gtest/gtest.h>
 
-#define EXPECT_OK(expression) \
-  EXPECT_EQ(util::error::OK, expression.error_code())
-#define ASSERT_OK(expression) \
-  ASSERT_EQ(util::error::OK, expression.error_code())
+#define EXPECT_OK(expression) EXPECT_EQ(error::OK, expression.error_code())
+#define ASSERT_OK(expression) ASSERT_EQ(error::OK, expression.error_code())
 
 #endif  // TESTING_GUNIT_H_