[proto2json] bug: enum type not parsed

[miklosbagi]

Example proto file:

syntax = "proto3";
package endlessloopbugtest;
option go_package = "github.com/miklosbagi/gopickers/bug";

service bugService {
	rpc BugMethod (BugRequest) returns (BugResponse);
}

message BugRequest {
    string id = 1;
}

message BugResponse {
	string bug_id = 1;
	enum EmbeddedEnumTest {
		TEST_ENUM_EMBEDDED = 0;
	}
    EmbeddedEnumTest embedded_enum = 2;
	EnumBug referenced_enum = 3;
}

enum EnumBug {
	ONE_TEST_ENUM = 0;
}

In both embedded and externally referenced enum scenarios, enum values are not pulled in.

Response:

{
    "bug_id": "c4a1c65e-c89b-4ee3-83ca-e00beb29540a",
    "embedded_enum": "ENUM_VALUE_MAX",
    "referenced_enum": "ENUM_VALUE_MAX"
}

Expected response:

{
    "bug_id": "c4a1c65e-c89b-4ee3-83ca-e00beb29540a",
    "embedded_enum": "0",
    "referenced_enum": "0"
}

Randomizing returned enum values based on options available is preferred.