Merge recent doc changes for OEMCrypto

This is a cherry pick of recent changes to OEMCrypto and ODK. Most of
these are part of the document migration to doxygen.

See http://go/wvgerrit/106005 and its parents for code reviews.

Bug: 144715340
Bug: 148232693
Bug: 167580674
Change-Id: I658f99c8117b974faed97322d61fac0f382283af

libwvdrmengine/oemcrypto/test/fuzz_tests/oemcrypto_fuzz_helper.cc

@@ -0,0 +1,25 @@
+// Copyright 2020 Google LLC. All Rights Reserved. This file and proprietary
+// source code may only be used and distributed under the Widevine Master
+// License Agreement.
+#include "oemcrypto_fuzz_helper.h"
+
+namespace wvoec {
+void RedirectStdoutToFile() { freopen("log.txt", "a", stdout); }
+
+std::vector<std::vector<uint8_t>> SplitInput(const uint8_t* data, size_t size) {
+  std::vector<std::vector<uint8_t>> result;
+  auto current_pos = data;
+  auto end = data + size;
+  // Using memmem to find separator
+  while (const uint8_t* pos = reinterpret_cast<const uint8_t*>(
+             memmem(current_pos, end - current_pos, kFuzzDataSeparator,
+                    sizeof(kFuzzDataSeparator)))) {
+    result.push_back({current_pos, pos});
+    current_pos = pos + sizeof(kFuzzDataSeparator);
+  }
+  if (current_pos < end) {
+    result.push_back({current_pos, end});
+  }
+  return result;
+}
+}  // namespace wvoec