Propagate control flow to bound double colon expressions

"Unused expression" should be reported on unused double colon expressions, this
is postponed

 #KT-12551 Open

compiler/testData/diagnostics/tests/callableReference/bound/controlFlow.kt

@@ -0,0 +1,23 @@
+fun unusedExpression(s: String) {
+    // TODO: report UNUSED_EXPRESSION (KT-12551)
+    s::hashCode
+    s::class
+}
+
+fun noUnusedParameter(s: String): Int {
+    val f = s::hashCode
+    return f()
+}
+
+fun unreachableCode(): Int {
+    (if (true) return 1 else return 0)::toString
+    <!UNREACHABLE_CODE!>return 0<!>
+}
+
+fun unreachableCodeInLoop(): Int {
+    while (true) {
+        (break)::toString
+        <!UNREACHABLE_CODE!>return 1<!>
+    }
+    return 2
+}

compiler/testData/diagnostics/tests/callableReference/bound/controlFlow.txt

@@ -0,0 +1,6 @@
+package
+
+public fun noUnusedParameter(/*0*/ s: kotlin.String): kotlin.Int
+public fun unreachableCode(): kotlin.Int
+public fun unreachableCodeInLoop(): kotlin.Int
+public fun unusedExpression(/*0*/ s: kotlin.String): kotlin.Unit

compiler/testData/diagnostics/tests/callableReference/ea81649_errorPropertyLHS.kt

@@ -15,6 +15,6 @@ data class User(val surname: String)
 
 fun foo() {
     bar<String> {
-        <!UNUSED_EXPRESSION!><!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>User<!>::<!OVERLOAD_RESOLUTION_AMBIGUITY!>surname<!><!>
+        <!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>User<!>::<!OVERLOAD_RESOLUTION_AMBIGUITY!>surname<!>
     }
 }