clang: Push the fix for #3277 into Type::declaration.

Fixes #3264.

Author: emilio

bindgen-tests/tests/expectations/tests/nested-class-field.rs

@@ -0,0 +1,7 @@
+class A {
+  class I;
+};
+
+class A::I {
+  int i;
+};

bindgen-tests/tests/headers/nested-class-field.hpp

@@ -1211,11 +1211,11 @@ impl Type {
 
     /// Get a cursor pointing to this type's declaration.
     pub(crate) fn declaration(&self) -> Cursor {
-        unsafe {
-            Cursor {
-                x: clang_getTypeDeclaration(self.x),
-            }
-        }
+        let decl = Cursor {
+            x: unsafe { clang_getTypeDeclaration(self.x) },
+        };
+        // Prior to clang 22, the declaration pointed to the definition.
+        decl.definition().unwrap_or(decl)
     }
 
     /// Get the canonical declaration of this type, if it is available.

bindgen/clang.rs

@@ -1269,12 +1269,6 @@ impl CompInfo {
         );
 
         let mut cursor = ty.declaration();
-
-        // If there is a definition, that's what we want.
-        if let Some(def) = cursor.definition() {
-            cursor = def;
-        }
-
         let mut kind = Self::kind_from_cursor(&cursor);
         if kind.is_err() {
             if let Some(location) = location {