Add fuzzers for import of WebCrypto DER-encoded keys.

components/webcrypto/rsa_import_key_spki_fuzzer.cc

Index: components/webcrypto/rsa_import_key_spki_fuzzer.cc
diff --git a/media/cdm/cenc_utils_fuzzertest.cc b/components/webcrypto/rsa_import_key_spki_fuzzer.cc
similarity index 65%
copy from media/cdm/cenc_utils_fuzzertest.cc
copy to components/webcrypto/rsa_import_key_spki_fuzzer.cc
index 8f656198d6d769c8a86585a9cd7025f9f5076714..e91b1403738b8f35258a74895ab741f9c1ce4679 100644
--- a/media/cdm/cenc_utils_fuzzertest.cc
+++ b/components/webcrypto/rsa_import_key_spki_fuzzer.cc
@@ -4,13 +4,12 @@
 
 #include <stddef.h>
 #include <stdint.h>
-#include <vector>
 
-#include "media/cdm/cenc_utils.h"
+#include "components/webcrypto/fuzzer_support.h"
 
 // Entry point for LibFuzzer.
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
-  std::vector<uint8_t> input(data, data + size);
-  media::ValidatePsshInput(input);
+  webcrypto::ImportRsaKeyFromDerFuzzData(data, size,
+                                         blink::WebCryptoKeyFormatSpki);
   return 0;
 }