[clang] [clang-format] Add KeepEmptyLines.AtEndOfBlock option (PR #224223)

[Björn Schäpers via cfe-commits]

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@@ -25609,6 +25611,51 @@ TEST_F(FormatTest, KeepEmptyLinesAtEOF) {
   verifyFormat(Code, "int i;\n\n\n", Style);
 }
 
+TEST_F(FormatTest, KeepEmptyLinesAtStartOfBlock) {
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HazardyKnusperkeks wrote:

`AtStartOfBlock` is by default `true`, so any test which does not set it to `false` tests it in some way or another.

https://github.com/llvm/llvm-project/pull/224223