Merge pull request #10087 from slavapestov/moar-test-coverage

Add a fixed crasher and an unfixed one

Author: slavapestov

validation-test/compiler_crashers_2/0105-sr5050.swift

@@ -0,0 +1,11 @@
+// RUN: not --crash %target-swift-frontend %s -typecheck
+
+protocol P {}
+
+func bar(p: P?) {
+  foo(p is String)
+}
+    
+func foo<T>(_: T, _: T) {}
+func foo<T>(_: T?, _: T?) {}
+

validation-test/compiler_crashers_2_fixed/0104-sr4388.swift

@@ -0,0 +1,11 @@
+// RUN: %target-swift-frontend %s -emit-ir
+
+class IndexPath {
+  init(indexes: [Int]) {}
+}
+
+extension CountableRange where Bound == Int {
+  func indexPaths(inSection section: Bound) -> [IndexPath]  {
+    return reduce([]) { $0 + [IndexPath(indexes: [section, $1])] } 
+  }
+}