Move annotations to canvas virtual (patchset #8 id:140001 of https://codereview.chromium.org/1744103002/ )"

Need to land chrome change first https://codereview.chromium.org/1766723003/

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1758023003

TBR=

Review URL: https://codereview.chromium.org/1758023003
diff --git a/src/utils/SkNWayCanvas.cpp b/src/utils/SkNWayCanvas.cpp
index e3b1e01..fd5fa82 100644
--- a/src/utils/SkNWayCanvas.cpp
+++ b/src/utils/SkNWayCanvas.cpp
@@ -292,6 +292,13 @@
     }
 }
 
+void SkNWayCanvas::onDrawAnnotation(const SkRect& rect, const char key[], SkData* data) {
+    Iter iter(fList);
+    while (iter.next()) {
+        iter->drawAnnotation(rect, key, data);
+    }
+}
+
 #ifdef SK_SUPPORT_LEGACY_DRAWFILTER
 SkDrawFilter* SkNWayCanvas::setDrawFilter(SkDrawFilter* filter) {
     Iter iter(fList);