Improve clang-format's stream formatting.

clang-format was a bit too aggressive when trying to keep labels and
values on the same line.

Before:
    llvm::outs()
         << "aaaaaaaaaaaaaaaaaaa: " << aaaaaaaaaaaaa(
                                           aaaaaaaaaaaaaaaaaaaaaaaaaaaa);
After:
  llvm::outs() << "aaaaaaaaaaaaaaaaaaa: "
               << aaaaaaaaaaaaa(aaaaaaaaaaaaaaaaaaaaaaaaaaaa);

llvm-svn: 182458
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 8c178d6..5ea531f 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -2360,6 +2360,8 @@
       "             << \"eeeeeeeeeeeeeeeee = \" << eeeeeeeeeeeeeeeee;");
   verifyFormat("llvm::outs() << aaaaaaaaaaaaaaaaaaaaaaaa << \"=\"\n"
                "             << bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb;");
+  verifyFormat("llvm::outs() << \"aaaaaaaaaaaaaaaaaaaaaaaa: \"\n"
+               "             << aaaaaaaaaaaaa(aaaaaaaaaaaaaaaaaaaaaaaaaaaa);");
 
   verifyFormat(
       "llvm::errs() << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\n"