Generate bridges for trait implementations properly

The intent was to keep the bridge codegen model as simple as possible: we
should be able to figure out all necessary bridges only by a minimal interface
that FunctionHandle provides (isAbstract, isDeclaration, getOverridden)

Add different tests for bridges

 #KT-318 Obsolete

compiler/testData/codegen/box/bridges/complexTraitImpl.kt

@@ -0,0 +1,28 @@
+import java.util.ArrayList
+import java.util.Arrays
+
+abstract class A {
+    abstract fun foo(): List<String>
+}
+
+trait B {
+    fun foo(): ArrayList<String> = ArrayList(Arrays.asList("B"))
+}
+
+open class C : A(), B
+
+trait D {
+    fun foo(): Collection<String>
+}
+
+class E : D, C()
+
+fun box(): String {
+    val e = E()
+    var r = e.foo()[0]
+    r += (e : D).foo().iterator().next()
+    r += (e : C).foo()[0]
+    r += (e : B).foo()[0]
+    r += (e : A).foo()[0]
+    return if (r == "BBBBB") "OK" else "Fail: $r"
+}