optimizations for wasm size (#582)

* optimize for size

* fix tests

* revert log feature

* make backtrace not optional

* remove dev feature from web dev-deps

packages/web/src/lib.rs

@@ -67,6 +67,7 @@ mod cfg;
 mod dom;
 #[cfg(any(feature = "hot-reload", debug_assertions))]
 mod hot_reload;
+#[cfg(feature = "hydrate")]
 mod rehydrate;
 // mod ric_raf;
 mod util;
@@ -164,7 +165,8 @@ where
 pub async fn run_with_props<T: 'static + Send>(root: Component<T>, root_props: T, cfg: Config) {
     let mut dom = VirtualDom::new_with_props(root, root_props);
 
-    if cfg!(feature = "panic_hook") && cfg.default_panic_hook {
+    #[cfg(feature = "panic_hook")]
+    if cfg.default_panic_hook {
         console_error_panic_hook::set_once();
     }
 
@@ -194,6 +196,8 @@ pub async fn run_with_props<T: 'static + Send>(root: Component<T>, root_props: T
         // it's a waste to produce edits just to get the vdom loaded
         let _ = dom.rebuild();
 
+        #[cfg(feature = "hydrate")]
+        #[allow(unused_variables)]
         if let Err(err) = websys_dom.rehydrate(&dom) {
             log::error!(
                 "Rehydration failed {:?}. Rebuild DOM into element from scratch",