[SPARK-18920][HISTORYSERVER]Update outdated date formatting

[WangTaoTheTonic]

What changes were proposed in this pull request?

Before we show "-" while the timestamp is less than 0, we should update it as now the date string is presented in format "yyyy-MM-dd ....."

How was this patch tested?

Before:

After:

[SparkQA]

Test build #70326 has finished for PR 16331 at commit 1618d1d.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[srowen]

I don't think this can be the right change -- it's construing any date before 2000 as invalid, which may happen to be OK but is pretty arbitrary. It arises as the result of formatting -1 as a date, and this method seems to try to handle that, but it's comparing the string to -1 I guess. Surely this should be handled elsewhere, like in whatever calls formatDate?

[srowen]

Ping @WangTaoTheTonic I don't think we can make this change -- can you investigate a more fundamental fix or close this?