1 files changed, 4 insertions, 1 deletions
diff --git a/Source/WebKit2/UIProcess/CoordinatedGraphics/CoordinatedBackingStore.cpp b/Source/WebKit2/UIProcess/CoordinatedGraphics/CoordinatedBackingStore.cpp
index 12afbc94e..dc1b213d4 100644
--- a/Source/WebKit2/UIProcess/CoordinatedGraphics/CoordinatedBackingStore.cpp
+++ b/Source/WebKit2/UIProcess/CoordinatedGraphics/CoordinatedBackingStore.cpp
@@ -140,6 +140,10 @@ void CoordinatedBackingStore::paintTilesToTextureMapper(Vector<TextureMapperTile
 
 void CoordinatedBackingStore::paintToTextureMapper(TextureMapper* textureMapper, const FloatRect& targetRect, const TransformationMatrix& transform, float opacity, BitmapTexture* mask)
 {
+    if (m_tiles.isEmpty())
+        return;
+    ASSERT(!m_size.isZero());
+
     Vector<TextureMapperTile*> tilesToPaint;
     Vector<TextureMapperTile*> previousTilesToPaint;
 
@@ -165,7 +169,6 @@ void CoordinatedBackingStore::paintToTextureMapper(TextureMapper* textureMapper,
         previousTilesToPaint.append(&tile);
     }
 
-    ASSERT(!m_size.isZero());
     FloatRect rectOnContents(FloatPoint::zero(), m_size);
     TransformationMatrix adjustedTransform = transform;
     // targetRect is on the contents coordinate system, so we must compare two rects on the contents coordinate system.