[clang] [clang-repl] Remove invalid TopLevelStmtDecl from TU on parse failure (PR #153945)

[Vassil Vassilev via cfe-commits]

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@@ -91,6 +93,53 @@ TEST_F(InterpreterTest, IncrementalInputTopLevelDecls) {
   EXPECT_EQ("var2", DeclToString(*R2DeclRange.begin()));
 }
 
+TEST_F(InterpreterTest, BadIncludeDoesNotCorruptTU) {
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vgvassilev wrote:

Can you try to `.undo` a `TopLevelStmtDecl` instead and check if it triggers the same issue?

https://github.com/llvm/llvm-project/pull/153945