correct the new graphs resulting from various tests

(Now that variances are not part of signature.)

src/test/compile-fail/dep-graph-struct-signature.rs

@@ -58,13 +58,15 @@ mod signatures {
         fn method(&self, x: u32) { }
     }
 
-    #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
     struct WillChanges {
+        #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
         x: WillChange,
+        #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
         y: WillChange
     }
 
-    #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
+    // The fields change, not the type itself.
+    #[rustc_then_this_would_need(ItemSignature)] //~ ERROR no path
     fn indirect(x: WillChanges) { }
 }
 

src/test/compile-fail/dep-graph-type-alias.rs

@@ -23,15 +23,21 @@ fn main() { }
 #[rustc_if_this_changed]
 type TypeAlias = u32;
 
-#[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
+// The type alias directly affects the type of the field,
+// not the enclosing struct:
+#[rustc_then_this_would_need(ItemSignature)] //~ ERROR no path
 struct Struct {
+    #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
     x: TypeAlias,
     y: u32
 }
 
-#[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
+#[rustc_then_this_would_need(ItemSignature)] //~ ERROR no path
 enum Enum {
-    Variant1(TypeAlias),
+    Variant1 {
+        #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
+        t: TypeAlias
+    },
     Variant2(i32)
 }