Add taskId to bubble xml

* Save the bubble taskId to XML
* Doesn't increase version # of XML, just sets the taskId
  as INVALID_TASK_ID if it's the old XML without taskId

Test: atest BubbleXmlHelperTest
Bug: 179676966
Change-Id: Ied04458fb4715a3de32784378568495128b54163
7 files changed