Fix codesmell "or with 0" in generated flags

Signed-off-by: Daniel Egger <daniel@eggers-club.de>

[edmonds: From https://github.com/protobuf-c/protobuf-c/pull/523.]

[edmonds: Adjust find string from "0 |" to "0 | ", test against `== 0`
rather than `!= std::string::npos` so that the find/erase calls are
anchored to the same portion of the string.]

protoc-c/c_field.cc

@@ -159,6 +159,11 @@ void FieldGenerator::GenerateDescriptorInitializerGeneric(io::Printer* printer,
   if (oneof != NULL)
     variables["flags"] += " | PROTOBUF_C_FIELD_FLAG_ONEOF";
 
+  // Eliminate codesmell "or with 0"
+  if (variables["flags"].find("0 | ") == 0) {
+   variables["flags"].erase(0, 4);
+  }
+
   printer->Print("{\n");
   if (descriptor_->file()->options().has_optimize_for() &&
         descriptor_->file()->options().optimize_for() ==