`goog.getMsg`: add `example` and `original_code` fields to `opt_options`
`goog.getMsg`: add `example` and `original_code` fields to `opt_options`

These fields allow the code to tell closure-compiler what text
to use for the `<ph>` and `<ex>` tags in the XMB file it generates.

RELNOTES: `goog.getMsg`: add `example` and `original_code` fields to `opt_options`
PiperOrigin-RevId: 439352803
Change-Id: I8778dbe3629d196f215c580c0d29b71f14e254eb

google/closure-library,google/closure-library,google/closure-library,google/closure-library,google/closure-library