Address review comments

src/test/ui/attributes/obsolete-attr.rs

@@ -1,5 +1,4 @@
-// When denying at the crate level, be sure to not get random warnings from the
-// injected intrinsics by the compiler.
+// Obsolete attributes fall back to feature gated custom attributes.
 
 #[ab_isize="stdcall"] extern {} //~ ERROR attribute `ab_isize` is currently unknown
 

src/test/ui/attributes/obsolete-attr.stderr

@@ -1,5 +1,5 @@
 error[E0658]: The attribute `fixed_stack_segment` is currently unknown to the compiler and may have meaning added to it in the future
-  --> $DIR/lint-obsolete-attr.rs:6:3
+  --> $DIR/obsolete-attr.rs:5:3
    |
 LL | #[fixed_stack_segment] fn f() {}
    |   ^^^^^^^^^^^^^^^^^^^
@@ -8,7 +8,7 @@ LL | #[fixed_stack_segment] fn f() {}
    = help: add #![feature(custom_attribute)] to the crate attributes to enable
 
 error[E0658]: The attribute `ab_isize` is currently unknown to the compiler and may have meaning added to it in the future
-  --> $DIR/lint-obsolete-attr.rs:4:3
+  --> $DIR/obsolete-attr.rs:3:3
    |
 LL | #[ab_isize="stdcall"] extern {}
    |   ^^^^^^^^

src/test/ui/attributes/unknown-attr.rs

@@ -1,5 +1,4 @@
-// When denying at the crate level, be sure to not get random warnings from the
-// injected intrinsics by the compiler.
+// Unknown attributes fall back to feature gated custom attributes.
 
 #![feature(custom_inner_attributes)]
 

src/test/ui/attributes/unknown-attr.stderr

@@ -1,5 +1,5 @@
 error[E0658]: The attribute `mutable_doc` is currently unknown to the compiler and may have meaning added to it in the future
-  --> $DIR/lint-unknown-attr.rs:6:4
+  --> $DIR/unknown-attr.rs:5:4
    |
 LL | #![mutable_doc]
    |    ^^^^^^^^^^^
@@ -8,7 +8,7 @@ LL | #![mutable_doc]
    = help: add #![feature(custom_attribute)] to the crate attributes to enable
 
 error[E0658]: The attribute `dance` is currently unknown to the compiler and may have meaning added to it in the future
-  --> $DIR/lint-unknown-attr.rs:8:3
+  --> $DIR/unknown-attr.rs:7:3
    |
 LL | #[dance] mod a {}
    |   ^^^^^
@@ -17,7 +17,7 @@ LL | #[dance] mod a {}
    = help: add #![feature(custom_attribute)] to the crate attributes to enable
 
 error[E0658]: The attribute `dance` is currently unknown to the compiler and may have meaning added to it in the future
-  --> $DIR/lint-unknown-attr.rs:10:3
+  --> $DIR/unknown-attr.rs:9:3
    |
 LL | #[dance] fn main() {}
    |   ^^^^^