Bug 23159 – [betterC] scope(failure) use in betterC gives confusing error

``` void main() { scope(failure) { int a; } int b; } ``` Gives ``` $ dmd -betterC main.d Error: Cannot use try-catch statements with -betterC ``` Two problems here. One, there's no line number. Two, this does not give any indication to the user about the true cause of this error. Thankfully I knew what to look for because I knew that scope(failure) was lowered to a try catch from a dconf talk. Really, scope(success)/scope(failure) has no business being in betterC code and should get its own custom error message.

@RazvanN7 created dlang/dmd pull request #14184 "Fix Issue 23159 - [betterC] scope(failure) use in betterC gives confu…" fixing this issue: - Fix Issue 23159 - [betterC] scope(failure) use in betterC gives confusing error https://github.com/dlang/dmd/pull/14184

dlang/dmd pull request #14184 "Fix Issue 23159 - [betterC] scope(failure) use in betterC gives confu…" was merged into master: - 6905c3ce783419dd9711a56dd830ce9da37d6959 by RazvanN7: Fix Issue 23159 - [betterC] scope(failure) use in betterC gives confusing error https://github.com/dlang/dmd/pull/14184