clang-format: Make indentation after "<<" more consistent.

Before:
  Diag(aaaaaaaaaaaaaaaaaaaa, aaaaaaaa)
      << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(
	  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa);
  Diag(aaaaaaaaaaaaaaaaaaaa, aaaaaaaa)
      << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(
	     aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa)
      << aaa;

After:
  Diag(aaaaaaaaaaaaaaaaaaaa, aaaaaaaa)
      << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(
	     aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa);
  Diag(aaaaaaaaaaaaaaaaaaaa, aaaaaaaa)
      << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(
	     aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa)
      << aaa;

llvm-svn: 260517
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index da8167e..48269ca 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -5105,6 +5105,13 @@
                "    << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa;");
   verifyFormat("SemaRef.Diag(Loc, diag::note_for_range_begin_end)\n"
                "    << BEF << IsTemplate << Description << E->getType();");
+  verifyFormat("Diag(aaaaaaaaaaaaaaaaaaaa, aaaaaaaa)\n"
+               "    << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(\n"
+               "           aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa);");
+  verifyFormat("Diag(aaaaaaaaaaaaaaaaaaaa, aaaaaaaa)\n"
+               "    << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(\n"
+               "           aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa)\n"
+               "    << aaa;");
 
   verifyFormat(
       "llvm::errs() << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\n"