Bug 1494316 - Set enable_iterator_debugging; r=dmajor

This flag is not required and causes problems with mingw builds.

Differential Revision: https://phabricator.services.mozilla.com/D7101

--HG--
extra : moz-landing-system : lando

media/webrtc/trunk/build/config/BUILD.gn

@@ -23,7 +23,7 @@ declare_args() {
   # introduce extra locking to check the state of an iterator against the state
   # of the current object. For iterator- and thread-heavy code, this can
   # significantly slow execution.
-  enable_iterator_debugging = !build_with_mozilla
+  enable_iterator_debugging = true 
 }
 
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