Leave existing messages intact so that multiple-file messages are a strict extension. This will keep worker.min.js compatible with the main Fable repl

Author: davedawkins

src/fable-standalone/src/Worker/Shared.fs

@@ -36,7 +36,8 @@ type WorkerAnswer =
     | Loaded of version: string
     | LoadFailed
     | ParsedCode of errors: Fable.Standalone.Error[]
-    | CompilationFinished of jsCode: string[] * errors: Fable.Standalone.Error[] * stats: CompileStats
+    | CompilationFinished of jsCode: string * errors: Fable.Standalone.Error[] * stats: CompileStats
+    | CompilationsFinished of jsCode: string[] * errors: Fable.Standalone.Error[] * stats: CompileStats
     | CompilerCrashed of message: string
     | FoundTooltip of id: Guid * lines: string[]
     | FoundCompletions of id: Guid * Fable.Standalone.Completion[]

src/fable-standalone/src/Worker/Worker.fs

@@ -206,7 +206,7 @@ let rec loop (box: MailboxProcessor<WorkerRequest>) (state: State) = async {
     | Some fable, CompileCode(fsharpCode, otherFSharpOptions) ->
         try
             let! (jsCode,errors,stats) = compileCode fable FILE_NAME ([| FILE_NAME |])  ([| fsharpCode |]) otherFSharpOptions
-            CompilationFinished ([| jsCode |], errors, stats) |> state.Worker.Post
+            CompilationFinished (jsCode, errors, stats) |> state.Worker.Post
         with er ->
             JS.console.error er
             CompilerCrashed er.Message |> state.Worker.Post
@@ -233,7 +233,7 @@ let rec loop (box: MailboxProcessor<WorkerRequest>) (state: State) = async {
                         combineStats c f  // Stats
                     )
 
-            CompilationFinished combinedResults |> state.Worker.Post
+            CompilationsFinished combinedResults |> state.Worker.Post
         with er ->
             JS.console.error er
             CompilerCrashed er.Message |> state.Worker.Post