A client script containing "g_form.showfieldMsg" will cause a javascript error in the console if the system property "glide.ui.use_jelly_activity_stream" is set to false.

1. Navigate to affected instance. 
2. Create/Update system property "glide.ui.use_jelly_activity_stream" to value "false"
3. Open a problem record
4. Open devtools javascript console
5. Paste and execute the following code:
g_form.showFieldMsg('work_notes','Please provide justification for Assignment Group change.','error',true);

Expected behavior:-  Field message displayed

Actual behavior:-  Field message displayed and js console error below:
js_includes_doctype.jsx?v=12-10-2019_2030&lp=Sat_Dec_14_04_32_21_PST_2019&c=5_59:9981
at e.showFieldMsg (js_includes_doctype.jsx?v=12-10-2019_2030&lp=Sat_Dec_14_04_32_21_PST_2019&c=5_59:9981)
at <anonymous>:1:8

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