[SPARK-9462][SQL] Initialize nondeterministic expressions in code gen fallback mode.

[rxin]

No description provided.

[rxin]

@mengxr I think this fixes the problem you ran into.

cc @cloud-fan

[cloud-fan]

it should be

ctx.references.foreach(_.foreach {
  case n: Nondeterministic => n.setInitialValues()
  case _ =>
})

[cloud-fan]

and why not do initiliaztion in CodegenFallback?

[rxin]

ah yes

[rxin]

@cloud-fan updated.

[cloud-fan]

lgtm

[SparkQA]

Test build #38956 has finished for PR 7767 at commit 713ac3a.

• This patch fails Scala style tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #38946 has finished for PR 7767 at commit bb5c334.

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

[SparkQA]

Test build #38961 has finished for PR 7767 at commit ef3e2d9.

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