Add JetMultiDeclarationReference

A reference to component* functions

idea/testData/resolve/references/MultiDeclarationReference.kt

@@ -0,0 +1,15 @@
+package a
+
+class A() {
+}
+
+fun A.component1() = 1
+fun A.component2() = 1
+
+fun main(args: Array<String>) {
+    val (a,<caret> b) = A()
+}
+
+// MULTIRESOLVE
+// REF: (for A in a).component1()
+// REF: (for A in a).component2()

idea/testData/resolve/references/PairMultiDeclaration.kt

@@ -0,0 +1,10 @@
+package a
+
+fun main(args: Array<String>) {
+    val p = Pair(1, 2)
+    val (a, b<caret>) = p
+}
+
+// MULTIRESOLVE
+// REF: (in kotlin.Pair).component1()
+// REF: (in kotlin.Pair).component2()