Start on some unwritten SkRecord TODOs:

tests/RecordTest.cpp

+#include "Test.h"
+
+#include "SkRecord.h"
+#include "SkRecords.h"
+
+// Adds the area of any DrawRect command it sees into area.
+class AreaSummer {
+public:
+    explicit AreaSummer(int* area) : fArea(area) {}
+
+    template <typename T> void operator()(const T&) { }
+
+private:
+    int* fArea;
+};
+template <> void AreaSummer::operator()(const SkRecords::DrawRect& record) {
+    *fArea += (int) (record.rect.width() * record.rect.height());
+}
+
+// Scales out the bottom-right corner of any DrawRect command it sees by 2x.
+struct Stretch {
+    template <typename T> void operator()(T*) {}
+};
+template <> void Stretch::operator()(SkRecords::DrawRect* record) {
+    record->rect.fRight *= 2;
+    record->rect.fBottom *= 2;
+}
+
+// Basic tests for the low-level SkRecord code.
+DEF_TEST(Record, r) {
+    SkRecord record;
+
+    // Add a simple DrawRect command.
+    SkRect rect = SkRect::MakeWH(10, 10);
+    SkPaint paint;
+    SkNEW_PLACEMENT_ARGS(record.append<SkRecords::DrawRect>(), SkRecords::DrawRect, (rect, paint));
+
+    // Its area should be 100.
+    int area = 0;
+    record.visit(AreaSummer(&area));
+    REPORTER_ASSERT(r, area == 100);
+
+    // Scale 2x.  Now it's area should be 400.
+    record.mutate(Stretch());
+    area = 0;
+    record.visit(AreaSummer(&area));
+    REPORTER_ASSERT(r, area == 400);
+}