[Clang] Prevent Copying of LateParsedClass Instances (#109428)

Class clang::Parser::LateParsedClass owns resources that are freed in
its destructor but has no user-written assignment operator.
This commit explicitly deletes the copy constructor and copy assignment
operator for the LateParsedClass.

Author: smanna12

clang/include/clang/Parse/Parser.h

@@ -1355,6 +1355,10 @@ class Parser : public CodeCompletionHandler {
     void ParseLexedAttributes() override;
     void ParseLexedPragmas() override;
 
+    // Delete copy constructor and copy assignment operator.
+    LateParsedClass(const LateParsedClass &) = delete;
+    LateParsedClass &operator=(const LateParsedClass &) = delete;
+
   private:
     Parser *Self;
     ParsingClass *Class;