SkRecord: make culling work if SkRecordAnnotateCullingPairs is called.

tests/RecordCullingTest.cpp

+#include "Test.h"
+
+#include "SkRecord.h"
+#include "SkRecordCulling.h"
+#include "SkRecorder.h"
+#include "SkRecords.h"
+
+struct PushCullScanner {
+    template <typename T> void operator()(const T&) {}
+
+    SkTDArray<unsigned> fPopOffsets;
+};
+
+template <> void PushCullScanner::operator()(const SkRecords::PushCull& record) {
+    *fPopOffsets.append() = record.popOffset;
+}
+
+
+DEF_TEST(RecordCulling, r) {
+    SkRecord record;
+    SkRecorder recorder(&record, 1920, 1080);
+
+    recorder.drawRect(SkRect::MakeWH(1000, 10000), SkPaint());
+
+    recorder.pushCull(SkRect::MakeWH(100, 100));
+        recorder.drawRect(SkRect::MakeWH(10, 10), SkPaint());
+        recorder.drawRect(SkRect::MakeWH(30, 30), SkPaint());
+        recorder.pushCull(SkRect::MakeWH(5, 5));
+            recorder.drawRect(SkRect::MakeWH(1, 1), SkPaint());
+        recorder.popCull();
+    recorder.popCull();
+
+    SkRecordAnnotateCullingPairs(&record);
+
+    PushCullScanner scan;
+    record.visit(scan);
+
+    REPORTER_ASSERT(r, 2 == scan.fPopOffsets.count());
+    REPORTER_ASSERT(r, 6 == scan.fPopOffsets[0]);
+    REPORTER_ASSERT(r, 2 == scan.fPopOffsets[1]);
+}