EME: Specify the correct size for PSSH boxes in tests

media/cdm/cenc_utils_unittest.cc

Index: media/cdm/cenc_utils_unittest.cc
diff --git a/media/cdm/cenc_utils_unittest.cc b/media/cdm/cenc_utils_unittest.cc
index c124cbd2d21d686473636b8e22f522af38a29593..1b038ff4457bc1ee6c54d5ed6c340cb2f685f6c1 100644
--- a/media/cdm/cenc_utils_unittest.cc
+++ b/media/cdm/cenc_utils_unittest.cc
@@ -7,6 +7,8 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#include <limits>
+
 #include "base/logging.h"
 #include "base/macros.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -54,6 +56,7 @@ class CencUtilsTest : public testing::Test {
 
     box->reserve(size);
     // Add size.
+    DCHECK(size < std::numeric_limits<uint8_t>::max());
     box->push_back(0);
     box->push_back(0);
     box->push_back(0);