Add new message to support worker warmup

Author: shreyas-gopalakrishna

src/proto/FunctionRpc.proto

@@ -86,6 +86,13 @@ message StreamingMessage {
 
     // Host gets the list of function load responses
     FunctionLoadResponseCollection function_load_response_collection = 32;
+    
+    // Host sends required metadata to worker to warmup the worker
+    FunctionWarmupRequest function_warmup_request = 33;
+    
+    // Worker responds after warming up with the warmup result
+    FunctionWarmupResponse function_warmup_response = 34;
+    
   }
 }
 
@@ -416,6 +423,15 @@ message InvocationResponse {
   StatusResult result = 3;
 }
 
+message FunctionWarmupRequest {
+  // Full path of worker.config.json location
+  string worker_directory = 1;
+}
+
+message FunctionWarmupResponse {
+  StatusResult result = 1;
+}
+
 // Used to encapsulate data which could be a variety of types
 message TypedData {
   oneof data {