DIE: Pass ownership of children via std::unique_ptr rather than raw pointer.

This should reduce the chance of memory leaks like those fixed in
r207240.

There's still some unclear ownership of DIEs happening in DwarfDebug.
Pushing unique_ptr and references through more APIs should help expose
the cases where ownership is a bit fuzzy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207263 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/AsmPrinter/DwarfDebug.h

@@ -367,7 +367,7 @@ class DwarfDebug : public AsmPrinterHandler {
   DIE *constructScopeDIE(DwarfCompileUnit &TheCU, LexicalScope *Scope);
   /// A helper function to create children of a Scope DIE.
   DIE *createScopeChildrenDIE(DwarfCompileUnit &TheCU, LexicalScope *Scope,
-                              SmallVectorImpl<DIE *> &Children);
+                              SmallVectorImpl<std::unique_ptr<DIE>> &Children);
 
   /// \brief Emit initial Dwarf sections with a label at the start of each one.
   void emitSectionLabels();