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/cdm/core/include/cdm_engine.h

@@ -351,6 +351,9 @@ class CdmEngine {
   virtual CdmResponseType SetPlaybackId(const CdmSessionId& session_id,
                                         const std::string& playback_id);
 
+  virtual void SetUserId(uint32_t user_id) { user_id_ = user_id; }
+  virtual uint32_t GetUserId() const { return user_id_; }
+
  protected:
   friend class CdmEngineFactory;
 
@@ -394,6 +397,7 @@ class CdmEngine {
   FileSystem* file_system_;
   Clock clock_;
   std::string spoid_;
+  uint32_t user_id_;
 
   // Usage related variables
   // Used to isolate a single active usage information license.  Loading,

libwvdrmengine/cdm/core/src/oemcrypto_adapter_dynamic.cpp

@@ -435,6 +435,7 @@ class WatchDog {
     status_ = OEMCrypto_SUCCESS;
     gave_up_ = false;
     sandbox_id_ = sandbox_id;
+    uid_ = wvcdm::GetIpcCallingUid();
   }
 
   // Deleted by either thread.
@@ -449,6 +450,7 @@ class WatchDog {
   // Function called by new worker thread.
   static void RunWatchDog(void* watcher) {
     WatchDog* dog = reinterpret_cast<WatchDog*>(watcher);
+    wvcdm::SetLoggingUid(dog->uid_);
     dog->DoInit();
     dog->SignalDoneAndCleanUp();
   }
@@ -610,6 +612,7 @@ class WatchDog {
   bool running_;
   bool gave_up_;
   std::vector<uint8_t> sandbox_id_;
+  uint32_t uid_;
 };
 
 struct LevelSession {