[clang] [clang-format]: Add `Custom` to `ShortFunctionStyle`; add new AllowShortFunctionsOnASingleLineOptions for granular setup (PR #134337)

[Owen Pan via cfe-commits]

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@@ -1907,6 +1954,8 @@ FormatStyle getMozillaStyle() {
   FormatStyle MozillaStyle = getLLVMStyle();
   MozillaStyle.AllowAllParametersOfDeclarationOnNextLine = false;
   MozillaStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_Inline;
+  MozillaStyle.AllowShortFunctionsOnASingleLineOptions = {};
+  MozillaStyle.AllowShortFunctionsOnASingleLineOptions.Inline = true;
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owenca wrote:

Ditto.

https://github.com/llvm/llvm-project/pull/134337