WVDrmPlugin changes to query device CSR payload for prov 4

[ Merge of https://widevine-internal-review.googlesource.com/c/cdm/+/178891/ ]

Plugin to provide getPropertyByteArray("deviceSignedCsrPayload")
which returns the signed CSR payload for device registration. It
queries both BCC and device info to be set in plugin before calling this
getPropertyByteArray("deviceSignedCsrPayload") method. The returned csr
payload will be used by assemble the device CSR by the caller for device
registration.

Bug: 286556950
Test: build WV DRM plugin
Change-Id: Ie592f53497f6d391ff232fd02bd4e66ca857e0e4

libwvdrmengine/mediadrm/include/WVDrmPlugin.h

@@ -42,7 +42,7 @@ const OEMCrypto_Algorithm kInvalidCryptoAlgorithm =
     static_cast<OEMCrypto_Algorithm>(-1);
 
 class WVDrmPlugin : public ::aidl::android::hardware::drm::BnDrmPlugin,
-                     wvcdm::WvCdmEventListener {
+                    wvcdm::WvCdmEventListener {
  public:
   WVDrmPlugin(const android::sp<WvContentDecryptionModule>& cdm,
               const std::string& appPackageName,
@@ -462,6 +462,9 @@ class WVDrmPlugin : public ::aidl::android::hardware::drm::BnDrmPlugin,
 
   std::string mAppPackageName;
 
+  std::string mCertificateSigningRequestChallenge;
+  std::string mDeviceInfo;
+
   ::ndk::SpAIBinder createBinder() override;
 
   WvStatus queryProperty(const std::string& property,