[clang-format] Break consecutive string literals in text protos

[krasimir]

Summary

This patch fixes a bug where consecutive string literals in text protos were
put on the same line.

[alexfh]

LG. Thanks!

lib/Format/TokenAnnotator.cpp

if (Right.is(tok::r_brace) && Left.is(tok::l_brace) &&
               Style.AllowShortFunctionsOnASingleLine &
                   FormatStyle::SFS_InlineOnly);
   } else if (Style.Language == FormatStyle::LK_Java) {
     if (Right.is(tok::plus) && Left.is(tok::string_literal) && Right.Next &&
         Right.Next->is(tok::string_literal))
       return true;
   } else if (Style.Language == FormatStyle::LK_Cpp ||
              Style.Language == FormatStyle::LK_ObjC ||
-             Style.Language == FormatStyle::LK_Proto) {
+             Style.Language == FormatStyle::LK_Proto ||
+             Style.Language == FormatStyle::LK_TextProto) {
     if (Left.isStringLiteral() && Right.isStringLiteral())
       return true;
   }
 
   // If the last token before a '}', ']', or ')' is a comma or a trailing
   // comment, the intention is to insert a line break after it in order to make
   // shuffling around entries easier. Import statements, especially in
   // JavaScript, can be an exception to this rule.

unittests/Format/FormatTestTextProto.cpp

verifyFormat("aaaaaaaaaaa: <\n"
                "    ccccccccccccccccccccccc: <\n"
                "      operator: 1\n"
                "      operator: 2\n"
                "      operator { key: value }\n"
                "    >\n"
                "  >\n"
                ">");
 }
+
+TEST_F(FormatTestTextProto, BreaksConsecutiveStringLiterals) {
+  verifyFormat("ala: \"str1\"\n"
+               "     \"str2\"\n");
+}
+
 } // end namespace tooling
 } // end namespace clang