wvcdm: filter logs by app uid

This commit is a combination of the following:
* http://go/wvgerrit/117003
* http://go/wvgerrit/118303

Bug: 162255728
Test: MediaDrmTest#testGetLogMessages
Change-Id: I5699b64d5c4bab463e5b587595fa7d324dc1d93f

libwvdrmengine/mediacrypto/src_hidl/WVCryptoPlugin.cpp

@@ -15,6 +15,7 @@
 #include <iterator>
 
 #include "HidlTypes.h"
+#include "log.h"
 #include "mapErrors-inl.h"
 #include "OEMCryptoCENC.h"
 #include "openssl/sha.h"
@@ -56,12 +57,21 @@ using wvcdm::WvContentDecryptionModule;
 
 WVCryptoPlugin::WVCryptoPlugin(const void* data, size_t size,
                                const sp<WvContentDecryptionModule>& cdm)
-  : mCDM(cdm){
+  : mCDM(cdm),
+    mUserId(wvcdm::UNKNOWN_UID) {
   if (data != NULL) {
     mSessionId.assign(static_cast<const char *>(data), size);
   }
   if (!mCDM->IsOpenSession(mSessionId)) {
     mSessionId.clear();
+  } else {
+    mCDM->GetSessionUserId(mSessionId, &mUserId);
+  }
+}
+
+WVCryptoPlugin::~WVCryptoPlugin() {
+  if (wvcdm::UNKNOWN_UID != mUserId) {
+    wvcdm::SetLoggingUid(mUserId);
   }
 }