Add tests for obsolete issues

#KT-12008 Obsolete
 #KT-11881 Obsolete
 #KT-10822 Obsolete

compiler/testData/diagnostics/testsWithStdLib/inference/kt12008.kt

@@ -0,0 +1,12 @@
+// FULL_JDK
+
+import java.util.*
+
+fun foo(<!UNUSED_PARAMETER!>o<!>: Optional<String>) {}
+
+class Test(nullable: String?) {
+    private val nullableOptional = Optional.ofNullable(nullable)
+    fun doIt() {
+        foo(nullableOptional)
+    }
+}

compiler/testData/diagnostics/testsWithStdLib/inference/kt12008.txt

@@ -0,0 +1,12 @@
+package
+
+public fun foo(/*0*/ o: java.util.Optional<kotlin.String>): kotlin.Unit
+
+public final class Test {
+    public constructor Test(/*0*/ nullable: kotlin.String?)
+    private final val nullableOptional: java.util.Optional<kotlin.String>
+    public final fun doIt(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}