Fix loading container type from Java

Load immutable flexible upper bound for 'Iterable<? super T>'

We load 'Collection<? super CharSequence>' as 'MutableCollection<in CharSequence>'
instead of 'MutableCollection<in CharSequence>..Collection<*>'
because it's obviously not typesafe to use any 'Collection<*>'
as argument for such type.

But there'se nothing bad with loading 'Iterable<? super CharSequence>'
as 'MutableIterable<*>..Collection<*>'. Same for other declarations that have
covariant mutable representation (currently Iterator, ListIterator).

Also there are useful use-cases when it's neccessary to use 'Iterable<*>'
as an argument for parameter with type 'Iterable<? super T>' (see matchers.kt test).

NB: Star-projections appear in examples because types like 'Collection<in CharSequence>'
with conflicting use-site projections are invalid in Kotlin, but they are valid in Java.

compiler/testData/diagnostics/tests/j+k/contravariantIterable.txt

@@ -0,0 +1,14 @@
+package
+
+public fun test(/*0*/ x: kotlin.collections.List<kotlin.String>, /*1*/ y: kotlin.collections.List<*>, /*2*/ z: kotlin.collections.MutableList<*>, /*3*/ w: kotlin.collections.MutableList<in kotlin.CharSequence>): kotlin.Unit
+
+public open class A {
+    public constructor A()
+    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
+
+    // Static members
+    public open fun bar(/*0*/ x: kotlin.collections.(Mutable)Iterator<*>!): kotlin.Unit
+    public open fun foo(/*0*/ x: kotlin.collections.(Mutable)Iterable<*>!): kotlin.Unit
+}