KT-1781 Can't distinguish between two constructors

#KT-1781 Fixed

 Now, if foo() and foo(vararg bar) both match the call site, the first one is preferred

compiler/testData/diagnostics/tests/varargs/AmbiguousVararg.jet

@@ -0,0 +1,6 @@
+fun foo(vararg <!UNUSED_PARAMETER!>t<!> : String) = ""
+fun foo(vararg <!UNUSED_PARAMETER!>t<!> : Int) = ""
+
+fun test() {
+    <!OVERLOAD_RESOLUTION_AMBIGUITY!>foo()<!>
+}

compiler/testData/diagnostics/tests/varargs/NilaryVsVararg.jet

@@ -0,0 +1,10 @@
+fun foo0() : String = "noarg"
+
+fun foo0(vararg <!UNUSED_PARAMETER!>t<!> : Int) : String = "vararg"
+
+fun test0() {
+    foo0()
+    foo0(1)
+    val a = IntArray(0)
+    foo0(*a)
+}

compiler/testData/diagnostics/tests/varargs/UnaryVsVararg.jet

@@ -0,0 +1,9 @@
+fun foo1(<!UNUSED_PARAMETER!>a<!> : Int) : String = "noarg"
+
+fun foo1(<!UNUSED_PARAMETER!>a<!> : Int, vararg <!UNUSED_PARAMETER!>t<!> : Int) : String = "vararg"
+
+fun test1() {
+    foo1(1)
+    val a = IntArray(0)
+    foo1(1, *a)
+}

compiler/testData/diagnostics/tests/varargs/kt1781.jet

@@ -0,0 +1,13 @@
+// FILE: kotlin.kt
+fun foo() {
+  JavaClass()
+  JavaClass("")
+}
+
+// FILE: JavaClass.java
+
+public class JavaClass {
+    public JavaClass() {  }
+
+    public JavaClass(String... ss) {  }
+}