clang-format: Fix string breaking after "<<".

Before, clang-format would not break overly long string literals
following a "<<" with FormatStyle::AlwaysBreakBeforeMultilineStrings
being set.

llvm-svn: 187650
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 3a3164c..ba78995 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -5167,6 +5167,11 @@
                    "aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaa "
                    "aaaaaaaaaaaaaaaaaaaaaa\");",
                    getGoogleStyle()));
+  EXPECT_EQ("llvm::outs() << \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa \"\n"
+            "                \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\";",
+            format("llvm::outs() << "
+                   "\"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaa"
+                   "aaaaaaaaaaaaaaaaaaa\";"));
 
   FormatStyle AlignLeft = getLLVMStyleWithColumns(12);
   AlignLeft.AlignEscapedNewlinesLeft = true;