Revert "Revert "remove SfxPoolItemArrayBase_Impl typedef""

This reverts commit b0eecd2d.

Now that the necessary parent commits are in, we can re-apply this.

svl/source/inc/poolio.hxx

@@ -58,8 +58,6 @@ struct SfxPoolVersion_Impl
                     {}
 };
 
-typedef std::vector<SfxPoolItem*> SfxPoolItemArrayBase_Impl;
-
 typedef std::shared_ptr< SfxPoolVersion_Impl > SfxPoolVersion_ImplPtr;
 
 /**
@@ -121,7 +119,7 @@ struct SfxItemPool_Impl
     bool                            mbPersistentRefCounts;
 
     SfxItemPool_Impl( SfxItemPool* pMaster, const OUString& rName, sal_uInt16 nStart, sal_uInt16 nEnd )
-        : maPoolItems(nEnd - nStart + 1, static_cast<SfxPoolItemArray_Impl*>(nullptr))
+        : maPoolItems(nEnd - nStart + 1)
         , aName(rName)
         , maPoolDefaults(nEnd - nStart + 1)
         , ppStaticDefaults(nullptr)

svl/source/items/itempool.cxx

@@ -641,7 +641,7 @@ const SfxPoolItem& SfxItemPool::Put( const SfxPoolItem& rItem, sal_uInt16 nWhich
         pItemArr = pImpl->maPoolItems[nIndex];
     }
 
-    SfxPoolItemArrayBase_Impl::iterator ppFree;
+    std::vector<SfxPoolItem*>::iterator ppFree;
     bool ppFreeIsSet = false;
 
     // Is this a 'poolable' item - ie. should we re-use and return
@@ -688,7 +688,7 @@ const SfxPoolItem& SfxItemPool::Put( const SfxPoolItem& rItem, sal_uInt16 nWhich
         // Unconditionally insert; check for a recently freed place
         if (pItemArr->maFree.size() > 0)
         {
-            SfxPoolItemArrayBase_Impl::iterator itr = pItemArr->begin();
+            auto itr = pItemArr->begin();
             sal_uInt32 nIdx = pItemArr->maFree.back();
             pItemArr->maFree.pop_back();