[clang] [Format] Do not crash on non-null terminated strings (PR #131299)

[Björn Schäpers via cfe-commits]

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@@ -2031,6 +2031,7 @@ class SourceManagerForFile {
   // The order of these fields are important - they should be in the same order
   // as they are created in `createSourceManagerForFile` so that they can be
   // deleted in the reverse order as they are created.
+  std::string ContentBuffer;
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HazardyKnusperkeks wrote:

I think that would be useful.

https://github.com/llvm/llvm-project/pull/131299