[chromium] Pass SkBitmap by reference in WebNinePatchLayer::setBitmap and refactor

cc/blink/web_nine_patch_layer_impl.cc

Index: cc/blink/web_nine_patch_layer_impl.cc
diff --git a/cc/blink/web_nine_patch_layer_impl.cc b/cc/blink/web_nine_patch_layer_impl.cc
index 6b3eacf17c9baeba7c6c3d42a8906b3cffa29d03..65e6fdd071e73f1ea6ed588733e037fa0cc7161b 100644
--- a/cc/blink/web_nine_patch_layer_impl.cc
+++ b/cc/blink/web_nine_patch_layer_impl.cc
@@ -34,7 +34,7 @@ void WebNinePatchLayerImpl::setBitmap(SkBitmap bitmap,
                            bitmap.height() - aperture.height));
 }
 
-void WebNinePatchLayerImpl::setBitmap(SkBitmap bitmap) {
+void WebNinePatchLayerImpl::setBitmap(const SkBitmap& bitmap) {
   cc::NinePatchLayer* nine_patch =
       static_cast<cc::NinePatchLayer*>(layer_->layer());
   nine_patch->SetBitmap(bitmap);
@@ -52,10 +52,4 @@ void WebNinePatchLayerImpl::setBorder(const blink::WebRect& border) {
   nine_patch->SetBorder(gfx::Rect(border));
 }
 
-void WebNinePatchLayerImpl::setFillCenter(bool fill_center) {
-  cc::NinePatchLayer* nine_patch =
-      static_cast<cc::NinePatchLayer*>(layer_->layer());
-  nine_patch->SetFillCenter(fill_center);
-}
-
 }  // namespace cc_blink