[gn build] Port 07a1d47

Author: llvmgnsyncbot

llvm/utils/gn/secondary/lldb/tools/lldb-dap/BUILD.gn

@@ -72,6 +72,7 @@ static_library("lib") {
     "OutputRedirector.cpp",
     "ProgressEvent.cpp",
     "Protocol/ProtocolBase.cpp",
+    "Protocol/ProtocolEvents.cpp",
     "Protocol/ProtocolRequests.cpp",
     "Protocol/ProtocolTypes.cpp",
     "ProtocolUtils.cpp",