Check proto argument in arguments for service

Commit f5ea44c adds pid information for non-proto dump.
But the common usage of tests pass the proto argument
for the target service instead of dumpsys, e.g.
 dumpsys activity --proto activities
In this case, asProto is still false that leads to the
pid information in text format is contained in proto dump.

Fix: 141371622
Test: atest DumpsysTest
Test: atest DisplaySizeTest
Change-Id: I6b3fb180985b33e7c97849556f8ba47b4776ca86
diff --git a/cmds/dumpsys/dumpsys.cpp b/cmds/dumpsys/dumpsys.cpp
index 68b3907..7646285 100644
--- a/cmds/dumpsys/dumpsys.cpp
+++ b/cmds/dumpsys/dumpsys.cpp
@@ -201,7 +201,13 @@
             if (i == optind) {
                 services.add(String16(argv[i]));
             } else {
-                args.add(String16(argv[i]));
+                const String16 arg(argv[i]);
+                args.add(arg);
+                // For backward compatible, if the proto argument is passed to the service, the
+                // dump request is also considered to use proto.
+                if (!asProto && !arg.compare(String16(PriorityDumper::PROTO_ARG))) {
+                    asProto = true;
+                }
             }
         }
     }