Merge pull request swiftlang#6307 from practicalswift/swiftc-28580-hastype-e-expected-type-to-have-been-set

[swiftc (104 vs. 5287)] Add crasher in swift::constraints::ConstraintSystem::getType(...)

Author: practicalswift

validation-test/compiler_crashers/28580-hastype-e-expected-type-to-have-been-set.swift

@@ -0,0 +1,10 @@
+// This source file is part of the Swift.org open source project
+// Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+
+// RUN: not --crash %target-swift-frontend %s -emit-ir
+// REQUIRES: asserts
+class B{lazy var f=[(n:{