Defer saves() until they're needed

tests/RecordReplaceDrawTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #if SK_SUPPORT_GPU
 
 #include "Test.h"
@@ skipping 34 matching lines @@
 
         pic.reset(recorder.endRecording());
     }
 
     SkRecord rerecord;
     SkRecorder canvas(&rerecord, kWidth, kHeight);
 
     JustOneDraw callback;
     GrRecordReplaceDraw(pic, &canvas, NULL, SkMatrix::I(), &callback);
 
-    REPORTER_ASSERT(r, 3 == rerecord.count());
-    assert_type<SkRecords::Save>(r, rerecord, 0);
-    assert_type<SkRecords::DrawRect>(r, rerecord, 1);
-    assert_type<SkRecords::Restore>(r, rerecord, 2);
+    switch (rerecord.count()) {
+        case 3:
+            assert_type<SkRecords::Save>(r, rerecord, 0);
+            assert_type<SkRecords::DrawRect>(r, rerecord, 1);
+            assert_type<SkRecords::Restore>(r, rerecord, 2);
+            break;
+        case 1:
+            assert_type<SkRecords::DrawRect>(r, rerecord, 0);
+            break;
+        default:
+            REPORTER_ASSERT(r, false);
+    }
 }
 
 // Make sure GrRecordReplaceDraw balances unbalanced saves
 DEF_TEST(RecordReplaceDraw_Unbalanced, r) {
     SkAutoTUnref<const SkPicture> pic;
 
     {
         SkPictureRecorder recorder;
         SkCanvas* canvas = recorder.beginRecording(SkIntToScalar(kWidth), SkIntToScalar(kHeight));
 
         // We won't balance this, but GrRecordReplaceDraw will for us.
         canvas->save();
-
+        canvas->scale(2, 2);
         pic.reset(recorder.endRecording());
     }
 
     SkRecord rerecord;
     SkRecorder canvas(&rerecord, kWidth, kHeight);
 
     GrRecordReplaceDraw(pic, &canvas, NULL, SkMatrix::I(), NULL/*callback*/);
 
-    REPORTER_ASSERT(r, 4 == rerecord.count());
-    assert_type<SkRecords::Save>(r, rerecord, 0);
-    assert_type<SkRecords::Save>(r, rerecord, 1);
-    assert_type<SkRecords::Restore>(r, rerecord, 2);
-    assert_type<SkRecords::Restore>(r, rerecord, 3);
+    // ensure rerecord is balanced (in this case by checking that the count is even)
+    REPORTER_ASSERT(r, (rerecord.count() & 1) == 0);
 }
 
 // Test out the layer replacement functionality with and w/o a BBH
 void test_replacements(skiatest::Reporter* r, GrContext* context, bool useBBH) {
     SkAutoTUnref<const SkPicture> pic;
 
     {
         SkRTreeFactory bbhFactory;
         SkPictureRecorder recorder;
         SkCanvas* canvas = recorder.beginRecording(SkIntToScalar(kWidth), SkIntToScalar(kHeight),
@@ skipping 25 matching lines @@
 
     SkAutoTUnref<GrTexture> texture(context->createUncachedTexture(desc, NULL, 0));
     layer->setTexture(texture, SkIRect::MakeWH(kWidth, kHeight));
 
     SkAutoTUnref<SkBBoxHierarchy> bbh;
 
     SkRecord rerecord;
     SkRecorder canvas(&rerecord, kWidth, kHeight);
     GrRecordReplaceDraw(pic, &canvas, layerCache, SkMatrix::I(), NULL/*callback*/);
 
-    REPORTER_ASSERT(r, 7 == rerecord.count());
-    assert_type<SkRecords::Save>(r, rerecord, 0);
-    assert_type<SkRecords::Save>(r, rerecord, 1);
-    assert_type<SkRecords::SetMatrix>(r, rerecord, 2);
-    assert_type<SkRecords::DrawBitmapRectToRect>(r, rerecord, 3);
-    assert_type<SkRecords::Restore>(r, rerecord, 4);
-    assert_type<SkRecords::DrawRect>(r, rerecord, 5);
-    assert_type<SkRecords::Restore>(r, rerecord, 6);
+    int recount = rerecord.count();
+    REPORTER_ASSERT(r, 5 == recount || 7 == recount);
+
+    int index = 0;
+    if (7 == recount) {
+        assert_type<SkRecords::Save>(r, rerecord, 0);
+        index += 1;
+    }
+    assert_type<SkRecords::Save>(r, rerecord, index + 0);
+    assert_type<SkRecords::SetMatrix>(r, rerecord, index + 1);
+    assert_type<SkRecords::DrawBitmapRectToRect>(r, rerecord, index + 2);
+    assert_type<SkRecords::Restore>(r, rerecord, index + 3);
+    assert_type<SkRecords::DrawRect>(r, rerecord, index + 4);
+    if (7 == recount) {
+        assert_type<SkRecords::Restore>(r, rerecord, 6);
+    }
 }
 
 DEF_GPUTEST(RecordReplaceDraw, r, factory) { 
     for (int type = 0; type < GrContextFactory::kLastGLContextType; ++type) {
         GrContextFactory::GLContextType glType = static_cast<GrContextFactory::GLContextType>(type);
         if (!GrContextFactory::IsRenderingGLContext(glType)) {
             continue;
         }
         GrContext* context = factory->get(glType);
         if (NULL == context) {
             continue;
         }
 
         test_replacements(r, context, true);
         test_replacements(r, context, false);
     }
 }
 
 #endif