make LayerIter private, and remove skipClip option

src/utils/SkCanvasStateUtils.cpp

Index: src/utils/SkCanvasStateUtils.cpp
diff --git a/src/utils/SkCanvasStateUtils.cpp b/src/utils/SkCanvasStateUtils.cpp
index 462636ead9fb593463991973aee6a0a53a7d943d..4ef5e2f731acf98a8b6c50b5f1d14ad80afb207d 100644
--- a/src/utils/SkCanvasStateUtils.cpp
+++ b/src/utils/SkCanvasStateUtils.cpp
@@ -222,7 +222,7 @@ SkCanvasState* SkCanvasStateUtils::CaptureCanvasState(SkCanvas* canvas) {
      */
     SkSWriter32<3*sizeof(SkCanvasLayerState)> layerWriter;
     int layerCount = 0;
-    for (SkCanvas::LayerIter layer(canvas, true/*skipEmptyClips*/); !layer.done(); layer.next()) {
+    for (SkCanvas::LayerIter layer(canvas); !layer.done(); layer.next()) {
 
         // we currently only work for bitmap backed devices
         SkPixmap pmap;