Adds proto support to the main app too.

src/objective-c/examples/Sample/Sample/ViewController.m

@@ -37,6 +37,7 @@
 #import <gRPC/GRPCMethodName.h>
 #import <gRPC/GRXWriter+Immediate.h>
 #import <gRPC/GRXWriteable.h>
+#import <RemoteTest/Messages.pb.h>
 
 @interface ViewController ()
 
@@ -50,16 +51,22 @@
 
   GRPCMethodName *method = [[GRPCMethodName alloc] initWithPackage:@"grpc.testing"
                                                          interface:@"TestService"
-                                                            method:@"EmptyCall"];
+                                                            method:@"UnaryCall"];
 
-  id<GRXWriter> requestsWriter = [GRXWriter writerWithValue:[NSData data]];
+  RMTSimpleRequest *request = [[[[[[RMTSimpleRequestBuilder alloc] init]
+                                  setResponseSize:100]
+                                 setFillUsername:YES]
+                                setFillOauthScope:YES]
+                               build];
+  id<GRXWriter> requestsWriter = [GRXWriter writerWithValue:[request data]];
 
   GRPCCall *call = [[GRPCCall alloc] initWithHost:@"grpc-test.sandbox.google.com"
                                            method:method
                                    requestsWriter:requestsWriter];
 
   id<GRXWriteable> responsesWriteable = [[GRXWriteable alloc] initWithValueHandler:^(NSData *value) {
-    NSLog(@"Received response: %@", value);
+    RMTSimpleResponse *response = [RMTSimpleResponse parseFromData:value];
+    NSLog(@"Received response: %@", response);
   } completionHandler:^(NSError *errorOrNil) {
     NSLog(@"Finished with error: %@", errorOrNil);
   }];