clang-format: Don't break lines starting with "import <string-literal>"

The author might be missing the "#" or these might be protocol buffer
definitions. Either way, we should not break the line or the string.

There don't seem to be other valid use cases.

llvm-svn: 199501
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index c75df9c..0fade5b 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -4657,6 +4657,10 @@
   verifyFormat("#if __has_include(<strstream>)\n"
                "#include <strstream>\n"
                "#endif");
+
+  // Protocol buffer definition or missing "#".
+  verifyFormat("import \"aaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaa\";",
+               getLLVMStyleWithColumns(30));
 }
 
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