Upgrade Closure Compiler to current

[dreamofabear]

Having just gone through this, I'm happy to work with whomever wants to pick this up to share knowledge. Don't really mind doing this myself either.

@rsimha @alabiaga Any interest?

[rsimha]

Happy to work on this.

[dreamofabear]

We can also split it up. 😄 There's about a year of updates left.

CC releases ~monthly. I'd recommend making each upgrade PR as small as possible to minimize risk.

[rsimha]

@choumx Was there a sweet spot you managed to identify when you initially attempted an upgrade to the latest version?

[dreamofabear]

I'd try the smallest upgrade possible first. https://github.com/google/closure-compiler/wiki/Binary-Downloads

[ampprojectbot]

This issue hasn't been updated in awhile. @rsimha Do you have any updates?

[rsimha]

#21618 has brought us to 20190301. There are still some outstanding fixes that we are awaiting in the next release. I'll close this issue once we adopt it.

[rsimha]

We're currently at the latest version of closure. Closing this in favor of #22452, which tracks the effort to dynamically generate runner.jar, so we can always be at the latest version.

[rsimha]

This is now truly done, and future updates should be automatic (modulo breaking changes). See #23759 (comment)

[rsimha]

One more success in the series: #24096