Certificate provisioning verification

bug: 8620943

This is a merge of changes made to the Widevine CDM
repository during certificate provisioning verification.

The following changes are included:

Fixes for certificate based licensing
https://widevine-internal-review.googlesource.com/#/c/5162/

Base64 encode and decode now handles non-multiple of 24-bits input
https://widevine-internal-review.googlesource.com/#/c/4981/

Fixed issues with device provisioning response handling
https://widevine-internal-review.googlesource.com/#/c/5153/

Persistent storage to support device certificates
https://widevine-internal-review.googlesource.com/#/c/5161/

Enable loading of certificates
https://widevine-internal-review.googlesource.com/#/c/5172/

Provide license server url
https://widevine-internal-review.googlesource.com/#/c/5173/

Change-Id: I0c032c1ae0055dcc1a7a77ad4b0ea0898030dc7d

libwvdrmengine/cdm/core/src/device_files.proto

@@ -0,0 +1,47 @@
+// ----------------------------------------------------------------------------
+// device_files.proto
+// ----------------------------------------------------------------------------
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Description:
+//   Format of various files stored at the device.
+//
+syntax = "proto2";
+
+package video_widevine_client.sdk;
+
+// need this if we are using libprotobuf-cpp-2.3.0-lite
+option optimize_for = LITE_RUNTIME;
+
+message DeviceCertificate {
+  optional bytes certificate = 1;
+  optional bytes wrapped_private_key = 2;
+}
+
+message License {
+  optional bytes key_set_id = 1;
+  optional bytes pssh_data = 2;
+  optional bytes license_request = 3;
+  optional bytes license = 4;
+}
+
+message File {
+  enum FileType {
+    DEVICE_CERTIFICATE = 1;
+    LICENSE = 2;
+  }
+
+  enum FileVersion {
+    VERSION_1 = 1;
+  }
+
+  optional FileType type = 1;
+  optional FileVersion version = 2 [default = VERSION_1];
+  optional DeviceCertificate device_certificate = 3;
+  repeated License licenses = 4;
+}
+
+message HashedFile {
+  optional bytes file = 1;
+  optional bytes hash = 2;
+}