Adjusts tests to expect type errors on default visibility.

test/libsolidity/syntaxTests/constructor/constructor_no_visibility.sol

@@ -1,3 +1,3 @@
 contract A { constructor() {} }
 // ----
-// Warning: (13-29): No visibility specified. Defaulting to "public".
+// SyntaxError: (13-29): No visibility specified.

test/libsolidity/syntaxTests/fallback/default_visibility.sol

@@ -3,4 +3,5 @@ contract C {
     function() {}
 }
 // ----
+// SyntaxError: (90-103): No visibility specified.
 // TypeError: (90-103): Fallback function must be defined as "external".

test/libsolidity/syntaxTests/visibility/function_no_visibility.sol

@@ -2,4 +2,4 @@ contract C {
     function f() pure { }
 }
 // ----
-// Warning: (17-38): No visibility specified. Defaulting to "public".
+// SyntaxError: (17-38): No visibility specified.

test/libsolidity/syntaxTests/visibility/function_no_visibility_050.sol

@@ -1,6 +0,0 @@
-pragma experimental "v0.5.0";
-contract C {
-    function f() pure { }
-}
-// ----
-// SyntaxError: (47-68): No visibility specified.

test/libsolidity/syntaxTests/visibility/interface/function_default.sol

@@ -2,4 +2,5 @@ interface I {
 	function f();
 }
 // ----
+// SyntaxError: (15-28): No visibility specified. Did you intend to add "public"?
 // TypeError: (15-28): Functions in interfaces must be declared external.

test/libsolidity/syntaxTests/visibility/interface/function_default050.sol

@@ -1,7 +0,0 @@
-pragma experimental "v0.5.0";
-interface I {
-	function f();
-}
-// ----
-// SyntaxError: (45-58): No visibility specified.
-// TypeError: (45-58): Functions in interfaces must be declared external.