Add regression tests for fixed fuzzball issues

tests/fuzzy/i9283.scala

@@ -0,0 +1,7 @@
+// AE-77a004382f0de9965cb3880b27f302eb1c885c48
+object Foo {
+    class A
+    def f(x: A): Unit = x { } // This error is necessary.
+}
+case class Foo()
+type Foo = Any

tests/fuzzy/i9284.scala

@@ -0,0 +1,7 @@
+// TUATE-a0aa3e4143e63305db9ebacb6165df0155d73bbd
+object Foo {
+    class Bar
+    Bar[String][Int]
+}
+
+class i0 { i0 [String][Int] }

tests/fuzzy/i9288.scala

@@ -0,0 +1,10 @@
+// AE-de752a30942c1949a413940222cd9e573e5aa6a4
+class Foo {
+    import annotation.static
+    class Bar
+    object Bar {
+        @static val x = 2
+    }
+    import Bar._
+    x
+}

tests/fuzzy/i9293.scala

@@ -0,0 +1,6 @@
+class Foo[X] {
+  def foo: X[X] = foo(null)
+}
+object Foo {
+  implicit def baz[X](arg: X): Foo[X] = ???
+}