clang-format: Increase penalty for wrapping array subscript expressions

Before:
  aaaaaaaaaaa aaaaaaaaaaaaaaa = aaaaaaaaaaaaaaaaaaaaaaaaaa->aaaaaaaaa[0].aaaaaaa
                                    [0].aaaaaaaaaaaaaaaaaaaaaa();

After:
  aaaaaaaaaaa aaaaaaaaaaaaaaa = aaaaaaaaaaaaaaaaaaaaaaaaaa->aaaaaaaaa[0]
                                    .aaaaaaa[0]
                                    .aaaaaaaaaaaaaaaaaaaaaa();

llvm-svn: 210529
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index baf05a9..a923e1a 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -5110,6 +5110,10 @@
 
   verifyGoogleFormat("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa<int>\n"
                      "    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa[aaaaaaaaaaaa];");
+  verifyFormat(
+      "aaaaaaaaaaa aaaaaaaaaaaaaaa = aaaaaaaaaaaaaaaaaaaaaaaaaa->aaaaaaaaa[0]\n"
+      "                                  .aaaaaaa[0]\n"
+      "                                  .aaaaaaaaaaaaaaaaaaaaaa();");
 }
 
 TEST_F(FormatTest, LineStartsWithSpecialCharacter) {