Lock down on the use of default values in patterns and types.

Per previous discussions, we only want to allow default values for
uncurried 'func' and 'constructor' parameters, and not for return
types or arbitrary tuple types. Introduce this restriction, fixing
part of <rdar://problem/13372694>. 



Swift SVN r6156

lib/Parse/Parser.cpp

@@ -435,38 +435,6 @@ bool Parser::parseList(tok RightK, SourceLoc LeftLoc, SourceLoc &RightLoc,
   return Invalid;
 }
 
-
-/// value-specifier:
-///   ':' type-annotation
-///   ':' type-annotation '=' expr
-///   '=' expr
-bool Parser::parseValueSpecifier(TypeLoc &Ty,
-                                 NullablePtr<Expr> &Init) {
-  // Diagnose when we don't have a type or an expression.
-  if (Tok.isNot(tok::colon) && Tok.isNot(tok::equal)) {
-    diagnose(Tok, diag::expected_type_or_init);
-    // TODO: Recover better by still creating var, but making it have
-    // 'invalid' type so that uses of the identifier are not errors.
-    return true;
-  }
-  
-  // Parse the type if present.
-  if (consumeIf(tok::colon) &&
-      parseTypeAnnotation(Ty, diag::expected_type))
-    return true;
-  
-  // Parse the initializer, if present.
-  if (consumeIf(tok::equal)) {
-    NullablePtr<Expr> Tmp = parseExpr(diag::expected_initializer_expr);
-    if (Tmp.isNull())
-      return true;
-    
-    Init = Tmp.get();
-  }
-  
-  return false;
-}
-
 /// diagnoseRedefinition - Diagnose a redefinition error, with a note
 /// referring back to the original definition.