Change Atlas recycling to track current flush count and recycle if Atlas not used in current flush.

src/gpu/GrAtlas.h

Index: src/gpu/GrAtlas.h
diff --git a/src/gpu/GrAtlas.h b/src/gpu/GrAtlas.h
index b6f25c210ab7fdccfa7a98a9b6ff1f22dfbc9341..cc09ab6da388694676aa1455648ed009e4190a77 100644
--- a/src/gpu/GrAtlas.h
+++ b/src/gpu/GrAtlas.h
@@ -36,26 +36,20 @@ public:
         }
     }
 
-    static void MarkAllUnused(GrAtlas* atlas) {
-        while (NULL != atlas) {
-            atlas->fUsed = false;
-            atlas = atlas->fNext;
-        }
-    }
-
-    static bool RemoveUnusedAtlases(GrAtlasMgr* atlasMgr, GrAtlas** startAtlas);
+    static bool RemoveUnusedAtlases(GrAtlasMgr* atlasMgr, GrAtlas** startAtlas,
+                                    uint64_t flushCount);
 
-    bool used() const { return fUsed; }
-    void setUsed(bool used) { fUsed = used; }
+    uint64_t lastFlush() const { return fLastFlush; }
+    void setLastFlush(uint64_t flush) { fLastFlush = flush; }
 
 private:
     GrAtlas(GrAtlasMgr*, int plotX, int plotY, GrMaskFormat format);
     ~GrAtlas(); // does not try to delete the fNext field
 
-    GrAtlas*        fNext;
-
     // for recycling
-    bool            fUsed;
+    uint64_t        fLastFlush;
+    
+    GrAtlas*        fNext;
 
     GrTexture*      fTexture;
     GrRectanizer*   fRects;