Inconsistent compiler prompt message when use --pause switch

[mstyura]

Description:
Run the compiler fsc.exe with the switch --pause (for example, to have a chance to attach a debugger) and pass some source files for compilation.
Compiler will prompt to press any key to continue, but implementation fscopts.fs#L764 actually uses read line and expect enter key.

Example:

E:\Projects\FSharp\Compiler>f4-1\net40\bin\fsc.exe test.fs --pause
Press any key to continue...
 Microsoft (R) F# Compiler version (private)
Copyright (c) Microsoft Corporation. All Rights Reserved.

Ok so far, but all of the subsequent prompts expect enter key

warning FS0075: The command-line option '--pause' is for test purposes only
[done 'Import mscorlib', entering 'Import mscorlib and FSharp.Core.dll'] press any key...
[done 'Import mscorlib and FSharp.Core.dll', entering 'Import system references'] press any key...
[done 'Import system references', entering 'Parse inputs'] press any key...
[done 'Parse inputs', entering 'Import non-system references'] press any key...
[done 'Import non-system references', entering 'Typecheck'] press any key...
[done 'Typecheck', entering 'Typechecked'] press any key...
[done 'Typechecked', entering 'Write Interface File'] press any key...
[done 'Write Interface File', entering 'Write XML document signatures'] press any key...
[done 'Write XML document signatures', entering 'Write XML docs'] press any key...
[done 'Write XML docs', entering 'Write HTML docs'] press any key...
[done 'Write HTML docs', entering 'Encode Interface Data'] press any key...
[done 'Encode Interface Data', entering 'Optimizations'] press any key...
[done 'Optimizations', entering 'Ending Optimizations'] press any key...
[done 'Ending Optimizations', entering 'Encoding OptData'] press any key...
[done 'Encoding OptData', entering 'TAST -> ILX'] press any key...

test.fs(1,81): warning FS0988: Main module of program is empty: nothing will happen when it is run
[done 'TAST -> ILX', entering 'ILX -> IL (Unions)'] press any key...
[done 'ILX -> IL (Unions)', entering 'ILX -> IL (Funcs)'] press any key...
[done 'ILX -> IL (Funcs)', entering 'Write .NET Binary'] press any key...
[done 'Write .NET Binary', entering 'Write Stats File'] press any key...
[done 'Write Stats File', entering 'Exiting'] press any key...

Expected:
Compiler continues when user press any key as specified in message OR compiler prompts to press enter.

Actual:
Compiler continues only after enter key.

Severity: Cosmetic

Version: 1251430

Workaround: Press enter key