[clang-format] Add SpaceBeforeCpp11BracedList option.

WebKit C++ style for object initialization is as follows:

  Foo foo { bar };

Yet using clang-format -style=webkit changes this to:

  Foo foo{ bar };

As there is no existing combination of rules that will ensure a space
before a braced list in this fashion, this patch adds a new
SpaceBeforeCpp11BracedList rule.

Patch by Ross Kirsling!

Differential Revision: https://reviews.llvm.org/D46024

llvm-svn: 334692
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 399503a..f234e28 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -7019,6 +7019,11 @@
                "  { \"ccccccccccccccccccccc\", 2 }\n"
                "};",
                ExtraSpaces);
+
+  FormatStyle SpaceBeforeBrace = getLLVMStyle();
+  SpaceBeforeBrace.SpaceBeforeCpp11BracedList = true;
+  verifyFormat("vector<int> x {1, 2, 3, 4};", SpaceBeforeBrace);
+  verifyFormat("f({}, {{}, {}}, MyMap[{k, v}]);", SpaceBeforeBrace);
 }
 
 TEST_F(FormatTest, FormatsBracedListsInColumnLayout) {
@@ -10622,6 +10627,7 @@
   CHECK_PARSE_BOOL(SpaceAfterCStyleCast);
   CHECK_PARSE_BOOL(SpaceAfterTemplateKeyword);
   CHECK_PARSE_BOOL(SpaceBeforeAssignmentOperators);
+  CHECK_PARSE_BOOL(SpaceBeforeCpp11BracedList);
   CHECK_PARSE_BOOL(SpaceBeforeCtorInitializerColon);
   CHECK_PARSE_BOOL(SpaceBeforeInheritanceColon);
   CHECK_PARSE_BOOL(SpaceBeforeRangeBasedForLoopColon);