Revert "Add platform_display impls for win32 and android"

src/android/mod.rs

@@ -189,7 +189,7 @@ impl Window {
     }
 
     pub fn platform_display(&self) -> *mut libc::c_void {
-        self.surface as *mut libc::c_void
+        self.display as *mut libc::c_void
     }
 }
 

src/win32/mod.rs

@@ -236,7 +236,7 @@ impl Window {
     }
 
     pub fn platform_display(&self) -> *mut libc::c_void {
-        self.window as *mut libc::c_void
+        unimplemented!()
     }
 }