private void ensureElementsIsMutable() {
        if (!((bitField0_ & 0x00000001) != 0)) {
          elements_ =
              new java.util.ArrayList<
                  com.google.cloud.workflows.executions.v1.Execution.StackTraceElement>(elements_);
          bitField0_ |= 0x00000001;
        }
      }
<pre>
A collection of stack elements (frames) where an error occurred.
</pre>

Protobuf type {@code google.cloud.workflows.executions.v1.Execution.StackTrace}
java-workflow-executions/proto-google-cloud-workflow-executions-v1/src/main/java/com/google/cloud/workflows/executions/v1/Execution.java