File util, generic crypto, and key query

This CL merges several CLs from the widevine repo:

http://go/wvgerrit/18012 Add support for querying allowed usage for key.
http://go/wvgerrit/17971 Add per-origin storage.
http://go/wvgerrit/18152 Add OEMCrypto's generic crypto operations to CDM.
http://go/wvgerrit/17911 QueryKeyControlInfo => QueryOemCryptoSessionId

Note: numbering in wv_cdm_types.h was added in this CL and will be
back ported to wvgerrit in a future CL.

Change-Id: Idb9e9a67e94f62f25dc16c5307f75a08b3430b64

libwvdrmengine/cdm/include/file_utils.h

@@ -0,0 +1,33 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+
+#include <string>
+#include <vector>
+
+#include "wv_cdm_types.h"
+
+namespace wvcdm {
+
+const char kCurrentDirectory[] = ".";
+const char kParentDirectory[] = "..";
+const char kDirectoryDelimiter = '/';
+const char kWildcard[] = "*";
+bool IsCurrentOrParentDirectory(char* dir);
+
+class FileUtils {
+ public:
+  static bool Exists(const std::string& src);
+  static bool Remove(const std::string& src);
+  static bool Copy(const std::string& src, const std::string& dest);
+  static bool List(const std::string& path, std::vector<std::string>* files);
+  static bool IsRegularFile(const std::string& path);
+  static bool IsDirectory(const std::string& path);
+  static bool CreateDirectory(const std::string& path);
+
+  // Certificate and offline licenses are now stored in security
+  // level specific directories. In an earlier version they were
+  // stored in a common directory and need to be copied over.
+  static void SecurityLevelPathBackwardCompatibility(
+      CdmSecurityLevel security_level);
+};
+
+}  // namespace wvcdm