improve commit 95eb921ec06ee7

   "tdf#108608 more Draw text editing responsiveness fixes"

lru_map is fine on Windows, was a bug in the new clear method I
added.

Change-Id: I27565675dfe0f57e2ba3c3e0c50297770761dc6a
Reviewed-on: https://gerrit.libreoffice.org/52728Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

include/o3tl/lru_map.hxx

@@ -125,7 +125,7 @@ public:
 
     const list_const_iterator_t end() const
     {
-        return mLruList.end();
+        return mLruList.cend();
     }
 
     size_t size() const
@@ -135,6 +135,7 @@ public:
 
     void clear()
     {
+        mLruMap.clear();
         mLruList.clear();
     }
 };

vcl/win/gdi/salfont.cxx

@@ -28,6 +28,7 @@
 #include <svsys.h>
 #include <vector>
 
+#include <o3tl/lru_map.hxx>
 #include <basegfx/matrix/b2dhommatrixtools.hxx>
 #include <basegfx/polygon/b2dpolygon.hxx>
 #include <i18nlangtag/mslangid.hxx>
@@ -57,10 +58,9 @@
 using namespace vcl;
 
 // GetGlyphOutlineW() seems to be a little slow, and doesn't seem to do it's own caching (tested on Windows10).
-// TODO use something a little smarter here like an LRU cache, and include the font as part of the cache key
+// TODO include the font as part of the cache key, then we won't need to clear it on font change
 // The cache limit is set by the rough number of characters needed to read your average Asian newspaper.
-constexpr size_t BOUND_RECT_CACHE_SIZE = 3000;
-static std::unordered_map<sal_GlyphId, tools::Rectangle> g_BoundRectCache;
+static o3tl::lru_map<sal_GlyphId, tools::Rectangle> g_BoundRectCache(3000);
 
 inline FIXED FixedFromDouble( double d )
 {
@@ -1340,8 +1340,6 @@ bool WinSalGraphics::GetGlyphBoundRect(const GlyphItem& rGlyph, tools::Rectangle
         rRect = it->second;
         return true;
     }
-    if (g_BoundRectCache.size() > BOUND_RECT_CACHE_SIZE)
-        g_BoundRectCache.clear();
 
     HDC hDC = getHDC();