Vendor dependencies

Let's see how I like this workflow.

vendor/wasm-bindgen-macro/ui-tests/invalid-methods.rs

@@ -0,0 +1,42 @@
+use wasm_bindgen::prelude::*;
+
+#[wasm_bindgen]
+pub struct A;
+
+#[wasm_bindgen]
+default impl A {
+}
+
+#[wasm_bindgen]
+unsafe impl A {
+}
+
+#[wasm_bindgen]
+impl Clone for A {
+}
+
+#[wasm_bindgen]
+impl<T> A {
+}
+
+#[wasm_bindgen]
+impl &'static A {
+}
+
+macro_rules! x { () => () }
+
+#[wasm_bindgen]
+impl A {
+    const X: u32 = 3;
+    type Y = u32;
+    x!();
+
+    // pub default fn foo() {} // TODO: compiler's pretty printer totally broken
+}
+
+#[wasm_bindgen]
+impl A {
+    pub const fn foo() {}
+}
+
+fn main() {}