Skipping the new default-hidden-visibility.rs test for WASM targets.

The test expectations don't apply to WASM, where the target spec
has a different default value of `default_hidden_visibility`.
See the test comments for more details.

Author: anforowicz

tests/codegen/default-hidden-visibility.rs

@@ -2,14 +2,21 @@
 // flag.  This is a regression test for https://github.com/rust-lang/compiler-team/issues/656.  See
 // also https://github.com/rust-lang/rust/issues/73295 and
 // https://github.com/rust-lang/rust/issues/37530.
+
+// We test 3 combinations of command-line flags:
+// * No extra command-line flag: DEFAULT
+// * Overriding to "yes": YES
+// * Overriding to "no": NO
 //
-// revisions:NONE YES NO
-//[YES] compile-flags: -Zdefault-hidden-visibility=yes
-//[NO]  compile-flags: -Zdefault-hidden-visibility=no
-//
+//     revisions:DEFAULT YES NO
+//     [YES] compile-flags: -Zdefault-hidden-visibility=yes
+//     [NO]  compile-flags: -Zdefault-hidden-visibility=no
+
 // `compiler/rustc_target/src/spec/base/wasm.rs` has a different default value of
 // `default_hidden_visibility` - it wouldn't match the test expectations below.
-// [NONE] ignore-wasm32
+// And therefore we skip this test on WASM:
+//
+//     ignore-wasm32
 
 // The test scenario is specifically about visibility of symbols exported out of dynamically linked
 // libraries.
@@ -22,8 +29,8 @@
 // .
 // We want to verify that the cmdline flag affects the visibility of this symbol:
 //
-// NONE: @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = constant
-// YES:  @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = hidden constant
-// NO:   @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = constant
+// DEFAULT: @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = constant
+// YES:     @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = hidden constant
+// NO:      @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = constant
 #[used]
 pub static exported_symbol: [u8; 6] = *b"foobar";