Generate compareTo() properly

Take into account:
1) resolved call to compareTo (instead of always calling Comparable's method)
2) types of both caller and callee, when primitive, to avoid wrong casting
(instead of always using caller's type)

 #KT-3078 Fixed

compiler/testData/codegen/operatorConventions/compareTo/extensionArray.kt

@@ -0,0 +1,16 @@
+fun checkLess(x: Array<Int>, y: Array<Int>) = when {
+    x >= y    -> "Fail $x >= $y"
+    !(x < y)  -> "Fail !($x < $y)"
+    !(x <= y) -> "Fail !($x <= $y)"
+    x > y     -> "Fail $x > $y"
+    x.compareTo(y) >= 0 -> "Fail $x.compareTo($y) >= 0"
+    else -> "OK"
+}
+
+fun Array<Int>.compareTo(other: Array<Int>) = size - other.size
+
+fun box(): String {
+    val a = Array<Int>(0, {0})
+    val b = Array<Int>(1, {0})
+    return checkLess(a, b)
+}