libwvhidl: implement API to get plugin logs

Bug: 162255728
Test: VtsHalDrmV1_4TargetTest
Change-Id: I333cb1ee2f25ae718e7f544f4a5f7ee50668041a

libwvdrmengine/mediadrm/include_hidl/WVDrmPlugin.h

@@ -220,6 +220,9 @@ struct WVDrmPlugin : public ::drm::V1_4::IDrmPlugin, IDrmPluginListener,
   Return<void> sendSessionLostState(
       const hidl_vec<uint8_t>& sessionId) override;
 
+  Return<void> getLogMessages(
+      getLogMessages_cb _hidl_cb) override;
+
   Return<bool> requiresSecureDecoder(const hidl_string& mime, SecurityLevel level)
       override;