Move SkRecordComputeLayers and CollectLayers into SkRecordDraw.cpp

src/gpu/GrPictureUtils.cpp

Index: src/gpu/GrPictureUtils.cpp
diff --git a/src/gpu/GrPictureUtils.cpp b/src/gpu/GrPictureUtils.cpp
index c0b53f96657dfa94e7e0f5b21bb4d034b86df82c..e8e965bb57d51b32855b28601a9895e79de6ed62 100644
--- a/src/gpu/GrPictureUtils.cpp
+++ b/src/gpu/GrPictureUtils.cpp
@@ -19,588 +19,3 @@ SkPicture::AccelData::Key GrAccelData::ComputeAccelDataKey() {
     return gGPUID;
 }
 
-// This looks silly, I know.  Why not just use SkRect::MakeLargest()?
-// In practice, this is well large enough, and it has a few extra advantages:
-// it fits in an SkIRect, and we can munge it a little in both SkRect and
-// SKIRect space without worrying about overflow.
-static const SkRect kUnbounded = { -2e9f, -2e9f, 2e9f, 2e9f };
-
-namespace SkRecords {
-
-// SkRecord visitor to gather saveLayer/restore information.
-class CollectLayers : SkNoncopyable {
-public:
-    CollectLayers(const SkRect& cullRect, const SkRecord& record,
-                  SkBBoxHierarchy* bbh, GrAccelData* accelData)
-        : fSaveLayersInStack(0)
-        , fAccelData(accelData) {
-
-        // Calculate bounds for all ops.  This won't go quite in order, so we'll need
-        // to store the bounds separately then feed them in to the BBH later in order.
-        fCTM = &SkMatrix::I();
-        fCurrentClipBounds = kUnbounded;
-
-        fBounds.reset(record.count());
-
-        for (fCurrentOp = 0; fCurrentOp < record.count(); ++fCurrentOp) {
-            record.visit<void>(fCurrentOp, *this);
-        }
-
-        // If we have any lingering unpaired Saves, simulate restores to make
-        // sure all ops in those Save blocks have their bounds calculated.
-        while (!fSaveStack.isEmpty()) {
-            this->popSaveBlock();
-        }
-
-        // Any control ops not part of any Save/Restore block draw everywhere.
-        while (!fControlIndices.isEmpty()) {
-            this->popControl(kUnbounded);
-        }
-
-        //--------- LAYER HOISTING
-        while (!fSaveLayerStack.isEmpty()) {
-            this->popSaveLayerInfo();
-        }
-        //--------- LAYER HOISTING
-
-        // Finally feed all stored bounds into the BBH.  They'll be returned in this order.
-        SkASSERT(bbh);
-        bbh->insert(&fBounds, record.count());
-    }
-
-    template <typename T> void operator()(const T& op) {
-        this->updateCTM(op);
-        this->updateClipBounds(op);
-        this->trackBounds(op);
-        //--------- LAYER HOISTING
-        this->trackSaveLayers(op);
-        //--------- LAYER HOISTING
-    }
-
-private:
-    // In this file, SkRect are in local coordinates, Bounds are translated back to identity space.
-    typedef SkRect Bounds;
-
-    struct SaveBounds {
-        int controlOps;        // Number of control ops in this Save block, including the Save.
-        Bounds bounds;         // Bounds of everything in the block.
-        const SkPaint* paint;  // Unowned.  If set, adjusts the bounds of all ops in this block.
-    };
-
-    //--------- LAYER HOISTING
-    class SaveLayerInfo {
-    public:
-        SaveLayerInfo() { }
-        SaveLayerInfo(int opIndex, bool isSaveLayer, const SkPaint* paint, const Bounds& clipBound)
-            : fStartIndex(opIndex)
-            , fIsSaveLayer(isSaveLayer)
-            , fHasNestedSaveLayer(false)
-            , fPaint(paint)
-            , fClipBound(clipBound) {
-        }
-
-        int            fStartIndex;
-        bool           fIsSaveLayer;
-        bool           fHasNestedSaveLayer;
-        const SkPaint* fPaint;
-        Bounds         fClipBound;
-    };
-    //--------- LAYER HOISTING
-
-    // Only Restore and SetMatrix change the CTM.
-    template <typename T> void updateCTM(const T&) {}
-    void updateCTM(const Restore& op)   { fCTM = &op.matrix; }
-    void updateCTM(const SetMatrix& op) { fCTM = &op.matrix; }
-
-    // Most ops don't change the clip.
-    template <typename T> void updateClipBounds(const T&) {}
-
-    // Clip{Path,RRect,Rect,Region} obviously change the clip.  They all know their bounds already.
-    void updateClipBounds(const ClipPath& op)   { this->updateClipBoundsForClipOp(op.devBounds); }
-    void updateClipBounds(const ClipRRect& op)  { this->updateClipBoundsForClipOp(op.devBounds); }
-    void updateClipBounds(const ClipRect& op)   { this->updateClipBoundsForClipOp(op.devBounds); }
-    void updateClipBounds(const ClipRegion& op) { this->updateClipBoundsForClipOp(op.devBounds); }
-
-    // The bounds of clip ops need to be adjusted for the paints of saveLayers they're inside.
-    void updateClipBoundsForClipOp(const SkIRect& devBounds) {
-        Bounds clip = SkRect::Make(devBounds);
-        // We don't call adjustAndMap() because as its last step it would intersect the adjusted
-        // clip bounds with the previous clip, exactly what we can't do when the clip grows.
-        fCurrentClipBounds = this->adjustForSaveLayerPaints(&clip) ? clip : kUnbounded;
-    }
-
-    // Restore holds the devBounds for the clip after the {save,saveLayer}/restore block completes.
-    void updateClipBounds(const Restore& op) {
-        // This is just like the clip ops above, but we need to skip the effects (if any) of our
-        // paired saveLayer (if it is one); it has not yet been popped off the save stack.  Our
-        // devBounds reflect the state of the world after the saveLayer/restore block is done,
-        // so they are not affected by the saveLayer's paint.
-        const int kSavesToIgnore = 1;
-        Bounds clip = SkRect::Make(op.devBounds);
-        fCurrentClipBounds =
-            this->adjustForSaveLayerPaints(&clip, kSavesToIgnore) ? clip : kUnbounded;
-    }
-
-    // We also take advantage of SaveLayer bounds when present to further cut the clip down.
-    void updateClipBounds(const SaveLayer& op)  {
-        if (op.bounds) {
-            // adjustAndMap() intersects these layer bounds with the previous clip for us.
-            fCurrentClipBounds = this->adjustAndMap(*op.bounds, op.paint);
-        }
-    }
-
-    // The bounds of these ops must be calculated when we hit the Restore
-    // from the bounds of the ops in the same Save block.
-    void trackBounds(const Save&)          { this->pushSaveBlock(NULL); }
-    void trackBounds(const SaveLayer& op)  { this->pushSaveBlock(op.paint); }
-    void trackBounds(const Restore&) { fBounds[fCurrentOp] = this->popSaveBlock(); }
-
-    void trackBounds(const SetMatrix&)         { this->pushControl(); }
-    void trackBounds(const ClipRect&)          { this->pushControl(); }
-    void trackBounds(const ClipRRect&)         { this->pushControl(); }
-    void trackBounds(const ClipPath&)          { this->pushControl(); }
-    void trackBounds(const ClipRegion&)        { this->pushControl(); }
-    void trackBounds(const PushCull&)          { this->pushControl(); }
-    void trackBounds(const PopCull&)           { this->pushControl(); }
-    void trackBounds(const BeginCommentGroup&) { this->pushControl(); }
-    void trackBounds(const AddComment&)        { this->pushControl(); }
-    void trackBounds(const EndCommentGroup&)   { this->pushControl(); }
-    void trackBounds(const DrawData&)          { this->pushControl(); }
-
-    // For all other ops, we can calculate and store the bounds directly now.
-    template <typename T> void trackBounds(const T& op) {
-        fBounds[fCurrentOp] = this->bounds(op);
-        this->updateSaveBounds(fBounds[fCurrentOp]);
-    }
-
-    void pushSaveBlock(const SkPaint* paint) {
-        // Starting a new Save block.  Push a new entry to represent that.
-        SaveBounds sb = { 0, Bounds::MakeEmpty(), paint };
-        fSaveStack.push(sb);
-        this->pushControl();
-    }
-
-    static bool PaintMayAffectTransparentBlack(const SkPaint* paint) {
-        if (paint) {
-            // FIXME: this is very conservative
-            if (paint->getImageFilter() || paint->getColorFilter()) {
-                return true;
-            }
-
-            // Unusual Xfermodes require us to process a saved layer
-            // even with operations outisde the clip.
-            // For example, DstIn is used by masking layers.
-            // https://code.google.com/p/skia/issues/detail?id=1291
-            // https://crbug.com/401593
-            SkXfermode* xfermode = paint->getXfermode();
-            SkXfermode::Mode mode;
-            // SrcOver is ok, and is also the common case with a NULL xfermode.
-            // So we should make that the fast path and bypass the mode extraction
-            // and test.
-            if (xfermode && xfermode->asMode(&mode)) {
-                switch (mode) {
-                    // For each of the following transfer modes, if the source
-                    // alpha is zero (our transparent black), the resulting
-                    // blended alpha is not necessarily equal to the original
-                    // destination alpha.
-                    case SkXfermode::kClear_Mode:
-                    case SkXfermode::kSrc_Mode:
-                    case SkXfermode::kSrcIn_Mode:
-                    case SkXfermode::kDstIn_Mode:
-                    case SkXfermode::kSrcOut_Mode:
-                    case SkXfermode::kDstATop_Mode:
-                    case SkXfermode::kModulate_Mode:
-                        return true;
-                        break;
-                    default:
-                        break;
-                }
-            }
-        }
-        return false;
-    }
-
-    Bounds popSaveBlock() {
-        // We're done the Save block.  Apply the block's bounds to all control ops inside it.
-        SaveBounds sb;
-        fSaveStack.pop(&sb);
-
-        // If the paint affects transparent black, we can't trust any of our calculated bounds.
-        const Bounds& bounds =
-            PaintMayAffectTransparentBlack(sb.paint) ? fCurrentClipBounds : sb.bounds;
-
-        while (sb.controlOps-- > 0) {
-            this->popControl(bounds);
-        }
-
-        // This whole Save block may be part another Save block.
-        this->updateSaveBounds(bounds);
-
-        // If called from a real Restore (not a phony one for balance), it'll need the bounds.
-        return bounds;
-    }
-
-    void pushControl() {
-        fControlIndices.push(fCurrentOp);
-        if (!fSaveStack.isEmpty()) {
-            fSaveStack.top().controlOps++;
-        }
-    }
-
-    void popControl(const Bounds& bounds) {
-        fBounds[fControlIndices.top()] = bounds;
-        fControlIndices.pop();
-    }
-
-    void updateSaveBounds(const Bounds& bounds) {
-        // If we're in a Save block, expand its bounds to cover these bounds too.
-        if (!fSaveStack.isEmpty()) {
-            fSaveStack.top().bounds.join(bounds);
-        }
-    }
-
-    // FIXME: this method could use better bounds
-    Bounds bounds(const DrawText&) const { return fCurrentClipBounds; }
-
-    Bounds bounds(const Clear&) const { return kUnbounded; }             // Ignores the clip.
-    Bounds bounds(const DrawPaint&) const { return fCurrentClipBounds; }
-    Bounds bounds(const NoOp&)  const { return Bounds::MakeEmpty(); }    // NoOps don't draw.
-
-    Bounds bounds(const DrawSprite& op) const {
-        const SkBitmap& bm = op.bitmap;
-
-        return Bounds::Make(SkIRect::MakeXYWH(op.left, op.top, bm.width(), bm.height()));  // Ignores the matrix.
-    }
-
-    Bounds bounds(const DrawRect& op) const { return this->adjustAndMap(op.rect, &op.paint); }
-    Bounds bounds(const DrawOval& op) const { return this->adjustAndMap(op.oval, &op.paint); }
-    Bounds bounds(const DrawRRect& op) const {
-        return this->adjustAndMap(op.rrect.rect(), &op.paint);
-    }
-    Bounds bounds(const DrawDRRect& op) const {
-        return this->adjustAndMap(op.outer.rect(), &op.paint);
-    }
-    Bounds bounds(const DrawImage& op) const {
-        const SkImage* image = op.image;
-        SkRect rect = SkRect::MakeXYWH(op.left, op.top,
-                                        SkIntToScalar(image->width()), SkIntToScalar(image->height()));
-
-        return this->adjustAndMap(rect, op.paint);
-    }
-    Bounds bounds(const DrawImageRect& op) const {
-        return this->adjustAndMap(op.dst, op.paint);
-    }
-    Bounds bounds(const DrawBitmapRectToRect& op) const {
-        return this->adjustAndMap(op.dst, op.paint);
-    }
-    Bounds bounds(const DrawBitmapNine& op) const {
-        return this->adjustAndMap(op.dst, op.paint);
-    }
-    Bounds bounds(const DrawBitmap& op) const {
-        const SkBitmap& bm = op.bitmap;
-        return this->adjustAndMap(SkRect::MakeXYWH(op.left, op.top, SkIntToScalar(bm.width()), SkIntToScalar(bm.height())),
-                                    op.paint);
-    }
-    Bounds bounds(const DrawBitmapMatrix& op) const {
-        const SkBitmap& bm = op.bitmap;
-        SkRect dst = SkRect::Make(SkIRect::MakeWH(bm.width(), bm.height()));
-        op.matrix.mapRect(&dst);
-        return this->adjustAndMap(dst, op.paint);
-    }
-
-    Bounds bounds(const DrawPath& op) const {
-        return op.path.isInverseFillType() ? fCurrentClipBounds
-            : this->adjustAndMap(op.path.getBounds(), &op.paint);
-    }
-    Bounds bounds(const DrawPoints& op) const {
-        SkRect dst;
-        dst.set(op.pts, op.count);
-
-        // Pad the bounding box a little to make sure hairline points' bounds aren't empty.
-        SkScalar stroke = SkMaxScalar(op.paint.getStrokeWidth(), 0.01f);
-        dst.outset(stroke / 2, stroke / 2);
-
-        return this->adjustAndMap(dst, &op.paint);
-    }
-    Bounds bounds(const DrawPatch& op) const {
-        SkRect dst;
-        dst.set(op.cubics, SkPatchUtils::kNumCtrlPts);
-        return this->adjustAndMap(dst, &op.paint);
-    }
-    Bounds bounds(const DrawVertices& op) const {
-        SkRect dst;
-        dst.set(op.vertices, op.vertexCount);
-        return this->adjustAndMap(dst, &op.paint);
-    }
-
-    Bounds bounds(const DrawPicture& op) const {
-        SkRect dst = op.picture->cullRect();
-        if (op.matrix) {
-            op.matrix->mapRect(&dst);
-        }
-        return this->adjustAndMap(dst, op.paint);
-    }
-
-    Bounds bounds(const DrawPosText& op) const {
-        const int N = op.paint.countText(op.text, op.byteLength);
-        if (N == 0) {
-            return Bounds::MakeEmpty();
-        }
-
-        SkRect dst;
-        dst.set(op.pos, N);
-        AdjustTextForFontMetrics(&dst, op.paint);
-        return this->adjustAndMap(dst, &op.paint);
-    }
-    Bounds bounds(const DrawPosTextH& op) const {
-        const int N = op.paint.countText(op.text, op.byteLength);
-        if (N == 0) {
-            return Bounds::MakeEmpty();
-        }
-
-        SkScalar left = op.xpos[0], right = op.xpos[0];
-        for (int i = 1; i < N; i++) {
-            left = SkMinScalar(left, op.xpos[i]);
-            right = SkMaxScalar(right, op.xpos[i]);
-        }
-        SkRect dst = { left, op.y, right, op.y };
-        AdjustTextForFontMetrics(&dst, op.paint);
-        return this->adjustAndMap(dst, &op.paint);
-    }
-    Bounds bounds(const DrawTextOnPath& op) const {
-        SkRect dst = op.path.getBounds();
-
-        // Pad all sides by the maximum padding in any direction we'd normally apply.
-        SkRect pad = { 0, 0, 0, 0 };
-        AdjustTextForFontMetrics(&pad, op.paint);
-
-        // That maximum padding happens to always be the right pad today.
-        SkASSERT(pad.fLeft == -pad.fRight);
-        SkASSERT(pad.fTop == -pad.fBottom);
-        SkASSERT(pad.fRight > pad.fBottom);
-        dst.outset(pad.fRight, pad.fRight);
-
-        return this->adjustAndMap(dst, &op.paint);
-    }
-
-    Bounds bounds(const DrawTextBlob& op) const {
-        SkRect dst = op.blob->bounds();
-        dst.offset(op.x, op.y);
-        return this->adjustAndMap(dst, &op.paint);
-    }
-
-    static void AdjustTextForFontMetrics(SkRect* rect, const SkPaint& paint) {
-#ifdef SK_DEBUG
-        SkRect correct = *rect;
-#endif
-        // crbug.com/373785 ~~> xPad = 4x yPad
-        // crbug.com/424824 ~~> bump yPad from 2x text size to 2.5x
-        const SkScalar yPad = 2.5f * paint.getTextSize(),
-            xPad = 4.0f * yPad;
-        rect->outset(xPad, yPad);
-#ifdef SK_DEBUG
-        SkPaint::FontMetrics metrics;
-        paint.getFontMetrics(&metrics);
-        correct.fLeft += metrics.fXMin;
-        correct.fTop += metrics.fTop;
-        correct.fRight += metrics.fXMax;
-        correct.fBottom += metrics.fBottom;
-        // See skia:2862 for why we ignore small text sizes.
-        SkASSERTF(paint.getTextSize() < 0.001f || rect->contains(correct),
-                    "%f %f %f %f vs. %f %f %f %f\n",
-                    -xPad, -yPad, +xPad, +yPad,
-                    metrics.fXMin, metrics.fTop, metrics.fXMax, metrics.fBottom);
-#endif
-    }
-
-    //--------- LAYER HOISTING
-    template <typename T> void trackSaveLayers(const T& op) {
-        /* most ops aren't involved in saveLayers */
-    }
-    void trackSaveLayers(const Save& s) { this->pushSaveLayerInfo(false, NULL); }
-    void trackSaveLayers(const SaveLayer& sl) {
-        this->pushSaveLayerInfo(true, sl.paint);
-    }
-    void trackSaveLayers(const Restore& r) { this->popSaveLayerInfo(); }
-    void trackSaveLayers(const DrawPicture& dp) {
-        // For sub-pictures, we wrap their layer information within the parent
-        // picture's rendering hierarchy
-        SkPicture::AccelData::Key key = GrAccelData::ComputeAccelDataKey();
-
-        const GrAccelData* childData = 
-            static_cast<const GrAccelData*>(dp.picture->EXPERIMENTAL_getAccelData(key));
-        if (!childData) {
-            // If the child layer hasn't been generated with saveLayer data we
-            // assume the worst (i.e., that it does contain layers which nest
-            // inside existing layers). Layers within sub-pictures that don't
-            // have saveLayer data cannot be hoisted.
-            // TODO: could the analysis data be use to fine tune this?
-            this->updateStackForSaveLayer();
-            return;
-        }
-
-        for (int i = 0; i < childData->numSaveLayers(); ++i) {
-            const GrAccelData::SaveLayerInfo& src = childData->saveLayerInfo(i);
-
-            Bounds newClip(fCurrentClipBounds);
-
-            if (!newClip.intersect(this->adjustAndMap(src.fBounds, dp.paint))) {
-                continue;
-            }
-
-            this->updateStackForSaveLayer();
-
-            GrAccelData::SaveLayerInfo& dst = fAccelData->addSaveLayerInfo();
-
-            // If src.fPicture is NULL the layer is in dp.picture; otherwise
-            // it belongs to a sub-picture.
-            dst.fPicture = src.fPicture ? src.fPicture : static_cast<const SkPicture*>(dp.picture);
-            dst.fPicture->ref();
-            dst.fBounds = newClip;
-            dst.fLocalMat = src.fLocalMat;
-            dst.fPreMat = src.fPreMat;
-            dst.fPreMat.postConcat(*fCTM);
-            if (src.fPaint) {
-                dst.fPaint = SkNEW_ARGS(SkPaint, (*src.fPaint));
-            }
-            dst.fSaveLayerOpID = src.fSaveLayerOpID;
-            dst.fRestoreOpID = src.fRestoreOpID;
-            dst.fHasNestedLayers = src.fHasNestedLayers;
-            dst.fIsNested = fSaveLayersInStack > 0 || src.fIsNested;
-        }
-    }
-
-    // Inform all the saveLayers already on the stack that they now have a
-    // nested saveLayer inside them
-    void updateStackForSaveLayer() {
-        for (int index = fSaveLayerStack.count() - 1; index >= 0; --index) {
-            if (fSaveLayerStack[index].fHasNestedSaveLayer) {
-                break;
-            }
-            fSaveLayerStack[index].fHasNestedSaveLayer = true;
-            if (fSaveLayerStack[index].fIsSaveLayer) {
-                break;
-            }
-        }
-    }
-
-    void pushSaveLayerInfo(bool isSaveLayer, const SkPaint* paint) {
-        if (isSaveLayer) {
-            this->updateStackForSaveLayer();
-            ++fSaveLayersInStack;
-        }
-
-        fSaveLayerStack.push(SaveLayerInfo(fCurrentOp, isSaveLayer, paint, fCurrentClipBounds));
-    }
-
-    void popSaveLayerInfo() {
-        if (fSaveLayerStack.count() <= 0) {
-            SkASSERT(false);
-            return;
-        }
-
-        SaveLayerInfo sli;
-        fSaveLayerStack.pop(&sli);
-
-        if (!sli.fIsSaveLayer) {
-            return;
-        }
-
-        --fSaveLayersInStack;
-
-        GrAccelData::SaveLayerInfo& slInfo = fAccelData->addSaveLayerInfo();
-
-        SkASSERT(NULL == slInfo.fPicture);  // This layer is in the top-most picture
-
-        slInfo.fBounds = fBounds[sli.fStartIndex];
-        slInfo.fBounds.intersect(sli.fClipBound);
-        slInfo.fLocalMat = *fCTM;
-        slInfo.fPreMat = SkMatrix::I();
-        if (sli.fPaint) {
-            slInfo.fPaint = SkNEW_ARGS(SkPaint, (*sli.fPaint));
-        }
-        slInfo.fSaveLayerOpID = sli.fStartIndex;
-        slInfo.fRestoreOpID = fCurrentOp;
-        slInfo.fHasNestedLayers = sli.fHasNestedSaveLayer;
-        slInfo.fIsNested = fSaveLayersInStack > 0;
-    }
-    //--------- LAYER HOISTING
-
-    // Returns true if rect was meaningfully adjusted for the effects of paint,
-    // false if the paint could affect the rect in unknown ways.
-    static bool AdjustForPaint(const SkPaint* paint, SkRect* rect) {
-        if (paint) {
-            if (paint->canComputeFastBounds()) {
-                *rect = paint->computeFastBounds(*rect, rect);
-                return true;
-            }
-            return false;
-        }
-        return true;
-    }
-
-    bool adjustForSaveLayerPaints(SkRect* rect, int savesToIgnore = 0) const {
-        for (int i = fSaveStack.count() - 1 - savesToIgnore; i >= 0; i--) {
-            if (!AdjustForPaint(fSaveStack[i].paint, rect)) {
-                return false;
-            }
-        }
-        return true;
-    }
-
-    // Adjust rect for all paints that may affect its geometry, then map it to identity space.
-    Bounds adjustAndMap(SkRect rect, const SkPaint* paint) const {
-        // Inverted rectangles really confuse our BBHs.
-        rect.sort();
-
-        // Adjust the rect for its own paint.
-        if (!AdjustForPaint(paint, &rect)) {
-            // The paint could do anything to our bounds.  The only safe answer is the current clip.
-            return fCurrentClipBounds;
-        }
-
-        // Adjust rect for all the paints from the SaveLayers we're inside.
-        if (!this->adjustForSaveLayerPaints(&rect)) {
-            // Same deal as above.
-            return fCurrentClipBounds;
-        }
-
-        // Map the rect back to identity space.
-        fCTM->mapRect(&rect);
-
-        // Nothing can draw outside the current clip.
-        // (Only bounded ops call into this method, so oddballs like Clear don't matter here.)
-        rect.intersect(fCurrentClipBounds);
-        return rect;
-    }
-
-    // Conservative identity-space bounds for each op in the SkRecord.
-    SkAutoTMalloc<Bounds> fBounds;
-
-    // We walk fCurrentOp through the SkRecord, as we go using updateCTM()
-    // and updateClipBounds() to maintain the exact CTM (fCTM) and conservative
-    // identity-space bounds of the current clip (fCurrentClipBounds).
-    unsigned fCurrentOp;
-    const SkMatrix* fCTM;
-    Bounds fCurrentClipBounds;
-
-    // Used to track the bounds of Save/Restore blocks and the control ops inside them.
-    SkTDArray<SaveBounds> fSaveStack;
-    SkTDArray<unsigned>   fControlIndices;
-
-    //--------- LAYER HOISTING
-    // Used to collect saveLayer information for layer hoisting
-    int                   fSaveLayersInStack;
-    SkTDArray<SaveLayerInfo> fSaveLayerStack;
-    GrAccelData*          fAccelData;
-    //--------- LAYER HOISTING
-};
-
-} // namespace SkRecords
-
-void SkRecordComputeLayers(const SkRect& cullRect, const SkRecord& record,
-                           SkBBoxHierarchy* bbh, GrAccelData* data) {
-    SkRecords::CollectLayers collector(cullRect, record, bbh, data);
-}
-
-