Resolve drawable when playing back DisplayListData in the RenderThread.

Drawables are mutable, and not expected to produce the same content if retained for longer than the
duration of the frame. This becomes relevant when recording multi-frame SKPs because the
serialization step forces drawables to be played back long after the frame completed. By resolving
the drawable when we are drawing the frame we avoid ref'ing the SkDrawable and do not extend its
lifetime beyond the frame.

Bug: skia:9234
Test: Captured SKPs on a Pixel 3
Change-Id: I5d317dd14e20be9d5e18675df8667327bd05aff0

1 files changed, 6 insertions, 1 deletions

diff --git a/libs/hwui/RecordingCanvas.cpp b/libs/hwui/RecordingCanvas.cpp
index e58fbbe8e667..c8eb1ca55910 100644
--- a/libs/hwui/RecordingCanvas.cpp
+++ b/libs/hwui/RecordingCanvas.cpp
@@ -274,7 +274,12 @@ struct DrawDrawable final : Op {
     }
     sk_sp<SkDrawable> drawable;
     SkMatrix matrix = SkMatrix::I();
-    void draw(SkCanvas* c, const SkMatrix&) const { c->drawDrawable(drawable.get(), &matrix); }
+    // It is important that we call drawable->draw(c) here instead of c->drawDrawable(drawable).
+    // Drawables are mutable and in cases, like RenderNodeDrawable, are not expected to produce the
+    // same content if retained outside the duration of the frame. Therefore we resolve
+    // them now and do not allow the canvas to take a reference to the drawable and potentially
+    // keep it alive for longer than the frames duration (e.g. SKP serialization).
+    void draw(SkCanvas* c, const SkMatrix&) const { drawable->draw(c, &matrix); }
 };
 struct DrawPicture final : Op {
     static const auto kType = Type::DrawPicture;