[Expressions] Debugger.Frame is not live error from evalWithDebugger

[jasonLaster]

Here is a slightly updated STR, it turns out this requires watch expressions. I reproduce this in Firefox 58-60.

STR:

• Open up attachment debugger-frame-bug.html in Nightly
• Open up the DevTools' Debugger
• Add the watch expression "asdf" (any expression really)
• Refresh and catch on the breakpoint.
• Comment out the "debugger" statement from the code in an editor.
• Refresh the page in Nightly.

Results:

evaluateJS: Error: Debugger.Frame is not live

Stack:
  evalWithDebugger@resource://devtools/server/actors/webconsole.js:1397:11
  onEvaluateJS@resource://devtools/server/actors/webconsole.js:949:20
  onPacket@resource://devtools/server/main.js:1767:15
  receiveMessage@resource://devtools/shared/transport/transport.js:760:7

https://bugzilla.mozilla.org/show_bug.cgi?id=1440472#c1

[jasonLaster]

#5524 was reverted

[jasonLaster]

I opened this bug, which proposes preventing expressions from pausing on exceptions: https://bugzilla.mozilla.org/show_bug.cgi?id=1448431