[clang-format] Add style option AllowShortLambdasOnASingleLine

Summary:
This option `AllowShortLambdasOnASingleLine` similar to the other `AllowShort*` options, but applied to C++ lambdas.

Reviewers: djasper, klimek

Reviewed By: klimek

Subscribers: MyDeveloperDay, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D57687

llvm-svn: 357027
diff --git a/clang/lib/Format/FormatToken.h b/clang/lib/Format/FormatToken.h
index 461e070..f54ffe9 100644
--- a/clang/lib/Format/FormatToken.h
+++ b/clang/lib/Format/FormatToken.h
@@ -65,6 +65,7 @@
   TYPE(JsTypeOperator)                                                         \
   TYPE(JsTypeOptionalQuestion)                                                 \
   TYPE(LambdaArrow)                                                            \
+  TYPE(LambdaLBrace)                                                           \
   TYPE(LambdaLSquare)                                                          \
   TYPE(LeadingJavaAnnotation)                                                  \
   TYPE(LineComment)                                                            \