clang-format: Improve format of lambdas in ctor initializers.

Before:
  Constructor()
      : Constructor([] { // comment
        int i;
      }) {}

After:
  Constructor()
      : Constructor([] { // comment
          int i;
        }) {}

llvm-svn: 225625
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index a49a35c1..3bb5540 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -9380,6 +9380,10 @@
   verifyFormat("string abc = SomeFunction(aaaaaaaaaaaaa, aaaaa, []() {\n"
                "  SomeOtherFunctioooooooooooooooooooooooooon();\n"
                "});");
+  verifyFormat("Constructor()\n"
+               "    : Field([] { // comment\n"
+               "        int i;\n"
+               "      }) {}");
 
   // Lambdas with return types.
   verifyFormat("int c = []() -> int { return 2; }();\n");