Recast draw_filter_into_device as drawDevice

src/core/SkCanvas.cpp

Index: src/core/SkCanvas.cpp
diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index 1999f3109fb8c907509518dfe6fd6b8062b92ac7..b434c5863e6dec8ce3448111477a3aed41cf99a9 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -1146,40 +1146,24 @@ int SkCanvas::saveLayer(const SaveLayerRec& origRec) {
     return this->getSaveCount() - 1;
 }
 
-static void draw_filter_into_device(SkBaseDevice* src, const SkImageFilter* filter,
-                                    SkBaseDevice* dst, const SkMatrix& ctm) {
-
-    SkBitmap srcBM;
-
-#if SK_SUPPORT_GPU
-    // TODO: remove this virtual usage of accessRenderTarget! It is preventing
-    // removal of the virtual on SkBaseDevice.
-    GrRenderTarget* srcRT = src->accessRenderTarget();
-    if (srcRT && !srcRT->asTexture() && dst->accessRenderTarget()) {
-        // When both the src & the dst are on the gpu but the src doesn't have a texture,
-        // we create a temporary texture for the draw.
-        // TODO: we should actually only copy the portion of the source needed to apply the image
-        // filter
-        GrContext* context = srcRT->getContext();
-        SkAutoTUnref<GrTexture> tex(context->textureProvider()->createTexture(srcRT->desc(),
-                                                                              SkBudgeted::kYes));
-
-        context->copySurface(tex, srcRT);
-
-        GrWrapTextureInBitmap(tex, src->width(), src->height(), src->isOpaque(), &srcBM);
-    } else
-#endif
-    {
-        srcBM = src->accessBitmap(false);
-    }
-
-    SkCanvas c(dst);
+void SkCanvas::DrawDeviceWithFilter(SkBaseDevice* src, const SkImageFilter* filter,
+                                    SkBaseDevice* dst, const SkMatrix& ctm,
+                                    const SkClipStack* clipStack) {
+    SkDraw draw;
+    SkRasterClip rc;
+    rc.setRect(SkIRect::MakeWH(dst->width(), dst->height()));
+    draw.fMatrix = &SkMatrix::I();
+    draw.fRC = &rc;
+    draw.fClipStack = clipStack;
+    draw.fDevice = dst;
 
     SkPaint p;
     p.setImageFilter(filter->makeWithLocalMatrix(ctm));
-    const SkScalar x = SkIntToScalar(src->getOrigin().x());
-    const SkScalar y = SkIntToScalar(src->getOrigin().y());
-    c.drawBitmap(srcBM, x, y, &p);
+
+    dst->drawDevice(draw, src,
+                    src->getOrigin().x() - dst->getOrigin().x(),
+                    src->getOrigin().y() - dst->getOrigin().y(),
+                    p);
 }
 
 static SkImageInfo make_layer_info(const SkImageInfo& prev, int w, int h, bool isOpaque,
@@ -1294,15 +1278,16 @@ void SkCanvas::internalSaveLayer(const SaveLayerRec& rec, SaveLayerStrategy stra
     }
     newDevice->setOrigin(ir.fLeft, ir.fTop);
 
-    if (rec.fBackdrop) {
-        draw_filter_into_device(priorDevice, rec.fBackdrop, newDevice, fMCRec->fMatrix);
-    }
-
     DeviceCM* layer = new DeviceCM(newDevice, paint, this, fConservativeRasterClip, stashedMatrix);
 
     layer->fNext = fMCRec->fTopLayer;
     fMCRec->fLayer = layer;
     fMCRec->fTopLayer = layer;    // this field is NOT an owner of layer
+
+    if (rec.fBackdrop) {
+        DrawDeviceWithFilter(priorDevice, rec.fBackdrop, newDevice,
+                             fMCRec->fMatrix, this->getClipStack());
+    }
 }
 
 int SkCanvas::saveLayerAlpha(const SkRect* bounds, U8CPU alpha) {