SkPDF: draw{Image,Bitmap} always serializes early

src/pdf/SkBitmapKey.h

+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#ifndef SkBitmapKey_DEFINED
+#define SkBitmapKey_DEFINED
+
+#include "SkBitmap.h"
+#include "SkImage.h"
+#include "SkCanvas.h"
+
+class SkBitmapKey {
+public:
+    SkBitmapKey() : fSubset(SkIRect::MakeEmpty()), fID(0) {}
+    explicit SkBitmapKey(const SkBitmap& bm)
+        : fSubset(bm.getSubset()), fID(bm.getGenerationID()) {}
+    explicit SkBitmapKey(const SkImage* img)
+        : fSubset(img ? img->bounds() : SkIRect::MakeEmpty())
+        , fID(img ? img->uniqueID() : 0) {}
+    explicit SkBitmapKey(const sk_sp<SkImage> img)
+        : fSubset(img->bounds()), fID(img->uniqueID()) {}
+    bool operator==(const SkBitmapKey& rhs) const {
+        return fID == rhs.fID && fSubset == rhs.fSubset;
+    }
+    bool operator!=(const SkBitmapKey& rhs) const { return !(*this == rhs); }
+
+private:
+    SkIRect fSubset;
+    uint32_t fID;
+};
+
+/**
+   This wraps a thing that could either be a bitmap or a image and
+   abstracts out some common tasks.
+ */
+class SkImageBitmap {
+public:
+    explicit SkImageBitmap(const SkBitmap& b) : fBitmap(b), fImage(nullptr) {}
+    explicit SkImageBitmap(SkImage* i) : fImage(i) { SkASSERT(fImage); }
+    SkIRect bounds() const { return fImage ? fImage->bounds() : fBitmap.bounds(); }
+    SkISize dimensions() const {
+        return fImage ? fImage->dimensions() : fBitmap.dimensions();
+    }
+    sk_sp<SkImage> makeImage() const {
+        return fImage ? sk_ref_sp(fImage) : SkImage::MakeFromBitmap(fBitmap);
+    }
+    SkBitmapKey getKey() const {
+        return fImage ? SkBitmapKey(fImage) : SkBitmapKey(fBitmap);
+    }
+    void draw(SkCanvas* canvas, SkPaint* paint) const {
+        if (fImage) {
+            canvas->drawImage(fImage, 0, 0, paint);
+        } else {
+            canvas->drawBitmap(fBitmap, 0, 0, paint);
+        }
+    }
+
+private:
+    SkBitmap fBitmap;
+    SkImage* fImage; // non-owning; when drawImage starts passing a sk_sp<>,
+                     // we can take a const ref to that sk_sp<>.
+};
+
+#endif  // SkBitmapKey_DEFINED