Correctly indent the RHS of 'is' and 'as' expressions.

test/splitting/mixed.stmt

Index: test/splitting/mixed.stmt
diff --git a/test/splitting/mixed.stmt b/test/splitting/mixed.stmt
index 33cdba44bf5f5023add63a19a9ba8f422f48079c..97ba50758a88a80d6afa5795236388e496fb364c 100644
--- a/test/splitting/mixed.stmt
+++ b/test/splitting/mixed.stmt
@@ -210,4 +210,16 @@ veryLongFunction() => longArgument + longArgument + longArgument;
 veryLongFunction() =>
     longArgument +
     longArgument +
-    longArgument;
+    longArgument;
+>>> initialize with as expression
+var longVariableName = identifierSoLongItWraps as SomeClassName;
+<<<
+var longVariableName =
+    identifierSoLongItWraps
+        as SomeClassName;
+>>> initialize with is expression
+var longVariableName = identifierSoLongItWraps is SomeClassName;
+<<<
+var longVariableName =
+    identifierSoLongItWraps
+        is SomeClassName;