This issue was originally filed by @mdakin

String toLowerCase and toUpperCase does not work correctly for Turkish dotless i and capital dotted i.

Run this application (Unfortunately http://try-dart-lang.appspot.com/ loses Turkish characters after I tried to link it):

main() {

  // Expected conversions
  String trUpper = "A,B,C,Ç,D,E,F,G,Ğ,H,I,İ,J,K,L,M,N,O,Ö,P,R,S,Ş,T,U,Ü,V,Y,Z";
  String trLower = "a,b,c,ç,d,e,f,g,ğ,h,ı,i,j,k,l,m,n,o,ö,p,r,s,ş,t,u,ü,v,y,z";
  
  // Actual conversions
  String dartTrUpper = trLower.toUpperCase();
  String dartTrLower = trUpper.toLowerCase();
  
  if (dartTrUpper != trUpper) {
    print ("Incorrect Turkish toUpper conversion. \nExpected: ${trUpper} \nFound: ${dartTrUpper}");
  }
  if (dartTrLower != trLower) {
    print ("Incorrect Turkish toLower conversion. \nExpected: ${trLower} \nFound: ${dartTrLower}");
  }
}

Expected: Program does not print anything.
Actual: Prints 2 messages with outputs.