Implement SkPicture::bytesUsed() for SkRecord backend

tests/PictureTest.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBBoxHierarchy.h"
 #include "SkBlurImageFilter.h"
 #include "SkCanvas.h"
@@ skipping 1703 matching lines @@
     SkCanvas* canvas = recorder.beginRecording(1, 1);
     canvas->drawARGB(255, 255, 255, 255);
     SkAutoTUnref<SkPicture> hasData(recorder.endRecording());
     // picture should have a non-zero id after recording
     REPORTER_ASSERT(reporter, hasData->uniqueID() != SK_InvalidGenID);
 
     // both pictures should have different ids
     REPORTER_ASSERT(reporter, hasData->uniqueID() != empty->uniqueID());
 }
 
+static void test_bytes_used(skiatest::Reporter* reporter) {
+    SkPictureRecorder recorder;
+
+    recorder.beginRecording(0, 0);
+    SkAutoTUnref<SkPicture> empty(recorder.endRecording());
+
+    // A SkPicture also has SkRecord and possibly SkBBHierarchy as members.

[mtklein, 2014/11/17 21:43:20]

As written, there will be no BBH.  Did you want to add one?

+    REPORTER_ASSERT(reporter, SkPictureUtils::approximateBytesUsed(empty.get()) >=
+                              sizeof(SkPicture));
+
+    // Protect against any unintentional bloat.
+    REPORTER_ASSERT(reporter, SkPictureUtils::approximateBytesUsed(empty.get()) <= 176);
+}
+
 DEF_TEST(Picture, reporter) {
 #ifdef SK_DEBUG
     test_deleting_empty_picture();
     test_serializing_empty_picture();
 #else
     test_bad_bitmap();
 #endif
     test_unbalanced_save_restores(reporter);
     test_peephole();
 #if SK_SUPPORT_GPU
     test_gpu_veto(reporter);
 #endif
     test_has_text(reporter);
     test_analysis(reporter);
     test_gatherpixelrefs(reporter);
     test_gatherpixelrefsandrects(reporter);
     test_bitmap_with_encoded_data(reporter);
     test_clip_bound_opt(reporter);
     test_clip_expansion(reporter);
     test_hierarchical(reporter);
     test_gen_id(reporter);
     test_savelayer_extraction(reporter);
+    test_bytes_used(reporter);
 }
 
 static void draw_bitmaps(const SkBitmap bitmap, SkCanvas* canvas) {
     const SkPaint paint;
     const SkRect rect = { 5.0f, 5.0f, 8.0f, 8.0f };
     const SkIRect irect =  { 2, 2, 3, 3 };
 
     // Don't care what these record, as long as they're legal.
     canvas->drawBitmap(bitmap, 0.0f, 0.0f, &paint);
     canvas->drawBitmapRectToRect(bitmap, &rect, rect, &paint, SkCanvas::kNone_DrawBitmapRectFlag);
@@ skipping 74 matching lines @@
 struct CountingBBH : public SkBBoxHierarchy {
     mutable int searchCalls;
 
     CountingBBH() : searchCalls(0) {}
 
     virtual void search(const SkRect& query, SkTDArray<unsigned>* results) const SK_OVERRIDE {
         this->searchCalls++;
     }
 
     virtual void insert(SkAutoTMalloc<SkRect>*, int) SK_OVERRIDE {}
+    virtual size_t bytesUsed() const { return 0; }
 };
 
 class SpoonFedBBHFactory : public SkBBHFactory {
 public:
     explicit SpoonFedBBHFactory(SkBBoxHierarchy* bbh) : fBBH(bbh) {}
     virtual SkBBoxHierarchy* operator()(int width, int height) const {
         return SkRef(fBBH);
     }
 private:
     SkBBoxHierarchy* fBBH;
@@ skipping 37 matching lines @@
 
     // The picture shares the immutable pixels but copies the mutable ones.
     REPORTER_ASSERT(r, mut.pixelRef()->unique());
     REPORTER_ASSERT(r, !immut.pixelRef()->unique());
 
     // When the picture goes away, it's just our bitmaps holding the refs.
     pic.reset(NULL);
     REPORTER_ASSERT(r, mut.pixelRef()->unique());
     REPORTER_ASSERT(r, immut.pixelRef()->unique());
 }