[clang] [clang] Use a formatted_raw_ostream in TextDiagnostic (PR #164935)

[via cfe-commits]

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@@ -59,11 +58,11 @@ static void applyTemplateHighlighting(raw_ostream &OS, StringRef Str,
 
     Str = Str.substr(Pos + 1);
     if (Normal)
-      OS.changeColor(templateColor, true);
+      OS.changeColor(templateColor, true, false);
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Sirraide wrote:

I’d just add a default argument of `false` to the `BG` parameter of `formatted_raw_ostream::changeColor`, because changing the background colour is a lot less common in my experience; that’d save us from having to update all these call sites here too.

https://github.com/llvm/llvm-project/pull/164935