Remove unused OEMCrypto_GenerateSignature fuzzer

Merged from https://widevine-internal-review.googlesource.com/174772
Merged from https://widevine-internal-review.googlesource.com/176633
Merged from https://widevine-internal-review.googlesource.com/176634
Merged from https://widevine-internal-review.googlesource.com/176670

Change-Id: I36438c102bfe68ff16eab3db301377e858f533c1

libwvdrmengine/oemcrypto/test/fuzz_tests/oemcrypto_generate_signature.cc

@@ -1,36 +0,0 @@
-#include "oemcrypto_fuzz_helper.h"
-#include "oemcrypto_session_tests_helper.h"
-#include "properties.h"
-
-static bool is_init = false;
-
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
-  wvoec::SessionUtil session_helper;
-  if (!is_init) {
-    wvoec::RedirectStdoutToFile();
-    wvoec::global_features.Initialize();
-    wvoec::global_features.RestrictFilter("*");
-    wvutil::Properties::Init();
-    is_init = true;
-  }
-
-  OEMCrypto_Initialize();
-  OEMCrypto_EnterTestMode();
-  session_helper.EnsureTestROT();
-
-  wvoec::Session s;
-  s.open();
-  s.GenerateDerivedKeysFromKeybox(session_helper.keybox_);
-
-  static const uint32_t SignatureBufferMaxLength = size;
-  vector<uint8_t> signature(SignatureBufferMaxLength);
-  size_t signature_length = signature.size();
-
-  OEMCryptoResult sts;
-  sts = OEMCrypto_GenerateSignature(s.session_id(), data, size,
-                                    &signature[0], &signature_length);
-
-  s.close();
-  OEMCrypto_Terminate();
-  return 0;
-}