test: More run-pass test fixes

src/test/auxiliary/cci_class_cast.rs

@@ -13,7 +13,7 @@ struct cat {
 }
 
     impl cat : ToStr {
-       pure fn to_str() -> ~str { self.name }
+       pure fn to_str() -> ~str { copy self.name }
     }
 
     priv impl cat {

src/test/auxiliary/issue-2631-a.rs

@@ -12,5 +12,5 @@ type header_map = HashMap<~str, @DVec<@~str>>;
 
 // the unused ty param is necessary so this gets monomorphized
 fn request<T: Copy>(req: header_map) {
-  let _x = *(*req.get(~"METHOD"))[0u];
+  let _x = *(copy *req.get(~"METHOD"))[0u];
 }

src/test/auxiliary/issue_2242_a.rs

@@ -6,5 +6,5 @@ trait to_strz {
 }
 
 impl ~str: to_strz {
-    fn to_strz() -> ~str { self }
+    fn to_strz() -> ~str { copy self }
 }

src/test/auxiliary/trait_inheritance_overloading_xc.rs

@@ -8,7 +8,7 @@ pub struct MyInt {
 }
 
 pub impl MyInt : Add<MyInt, MyInt> {
-    pure fn add(other: &MyInt) -> MyInt { mi(self.val + other.val) }
+    pure fn add(&self, other: &MyInt) -> MyInt { mi(self.val + other.val) }
 }
 
 pub impl MyInt : Sub<MyInt, MyInt> {