Merge pull request #11485 from ethereum/changelogForMod

Changelog entry for modifier fix.

Author: ekpyron

Changelog.md

@@ -19,6 +19,7 @@ Bugfixes:
  * Code Generator: Fix internal error when function arrays are assigned to storage variables and the function types can be implicitly converted but are not identical.
  * Code Generator: Fix internal error when super would have to skip an unimplemented function in the virtual resolution order.
  * Control Flow Graph: Take internal calls to functions that always revert into account for reporting unused or unassigned variables.
+ * Control Flow Graph: Assume unimplemented modifiers use a placeholder.
  * SMTChecker: Fix internal error on struct constructor with fixed bytes member initialized with string literal.
  * SMTChecker: Fix internal error on external calls from the constructor.
  * SMTChecker: Fix internal error on conversion from ``bytes`` to ``fixed bytes``.