pastojs: source map: prepend absolute source files with file://

compiler/packages/pastojs/src/pas2jscompiler.pp

@@ -2254,6 +2254,8 @@ begin
         MapFilename:=LocalFilename;
       end;
     end;
+    if FilenameIsAbsolute(MapFilename) then
+      MapFilename:='file://'+MapFilename;
     {$IFNDEF Unix}
     // use / as PathDelim
     if PathDelim<>'/' then