Implement SkRecordedDrawable::onApproximateBytesUsed

This allows recorded pictures finished as drawables to be used for glyph
drawing.

Change-Id: I717626eda2bf4e1659c8941c3217cb61c1a16cf4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/506882
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>

src/core/SkRecordedDrawable.cpp

@@ -13,6 +13,19 @@
 #include "src/core/SkRecordDraw.h"
 #include "src/core/SkRecordedDrawable.h"
 
+size_t SkRecordedDrawable::onApproximateBytesUsed() {
+    size_t drawablesSize = 0;
+    if (fDrawableList) {
+        for (auto&& drawable : *fDrawableList) {
+            drawablesSize += drawable->approximateBytesUsed();
+        }
+    }
+    return sizeof(*this) +
+           (fRecord ? fRecord->bytesUsed() : 0) +
+           (fBBH ? fBBH->bytesUsed() : 0) +
+           drawablesSize;
+}
+
 void SkRecordedDrawable::onDraw(SkCanvas* canvas) {
     SkDrawable* const* drawables = nullptr;
     int drawableCount = 0;

src/core/SkRecordedDrawable.h

@@ -25,6 +25,7 @@ public:
 
 protected:
     SkRect onGetBounds() override { return fBounds; }
+    size_t onApproximateBytesUsed() override;
 
     void onDraw(SkCanvas* canvas) override;
 

src/core/SkRecorder.h

@@ -25,6 +25,7 @@ public:
 
     int count() const { return fArray.count(); }
     SkDrawable* const* begin() const { return fArray.begin(); }
+    SkDrawable* const* end() const { return fArray.end(); }
 
     void append(SkDrawable* drawable);
 

src/core/SkScalerCache.cpp

@@ -84,6 +84,7 @@ std::tuple<SkDrawable*, size_t> SkScalerCache::prepareDrawable(SkGlyph* glyph) {
     size_t delta = 0;
     if (glyph->setDrawable(&fAlloc, fScalerContext.get())) {
         delta = glyph->drawable()->approximateBytesUsed();
+        SkASSERT(delta > 0);
     }
     return {glyph->drawable(), delta};
 }
@@ -91,15 +92,15 @@ std::tuple<SkDrawable*, size_t> SkScalerCache::prepareDrawable(SkGlyph* glyph) {
 std::tuple<SkDrawable*, size_t> SkScalerCache::mergeDrawable(SkGlyph* glyph,
                                                              sk_sp<SkDrawable> drawable) {
     SkAutoMutexExclusive lock{fMu};
-    size_t drawableDelta = 0;
+    size_t delta = 0;
     if (glyph->setDrawableHasBeenCalled()) {
         SkDEBUGFAIL("Re-adding drawable to existing glyph. This should not happen.");
     }
     if (glyph->setDrawable(&fAlloc, std::move(drawable))) {
-        drawableDelta = glyph->drawable()->approximateBytesUsed();
-        SkASSERT(drawableDelta > 0);
+        delta = glyph->drawable()->approximateBytesUsed();
+        SkASSERT(delta > 0);
     }
-    return {glyph->drawable(), drawableDelta};
+    return {glyph->drawable(), delta};
 }
 
 int SkScalerCache::countCachedGlyphs() const {