Added the framework for having canvas/recorder/picture record depth_set's.

tests/CanvasTest.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.
  */
 
 /*  Description:
  *      This test defines a series of elementatry test steps that perform
  *      a single or a small group of canvas API calls. Each test step is
@@ skipping 761 matching lines @@
     canvas.save();
     path.moveTo(5, 5);
     canvas.clipPath(path);
     canvas.restore();
     canvas.save();
     path.moveTo(7, 7);
     canvas.clipPath(path);  // should not assert here
     canvas.restore();
 }
 
+
+void test_updatedepth(skiatest::Reporter* reporter) {
+    // set some depths (with picture enabled), then check them as they get set
+    SkPictureRecorder recorder;
+    SkCanvas* canvas;
+    sk_sp<SkPicture> picture;
+
+    canvas = recorder.beginRecording(SkRect::MakeIWH(100, 100));
+
+    canvas->setZ(-10);
+    REPORTER_ASSERT(reporter, canvas->getZ() == -10);
+
+    canvas->save();
+    canvas->setZ(10);
+    REPORTER_ASSERT(reporter, canvas->getZ() == 10);
+
+    canvas->restore();
+    REPORTER_ASSERT(reporter, canvas->getZ() == -10);
+
+    canvas->setZ(3.14);
+    REPORTER_ASSERT(reporter, canvas->getZ() == 3.14);
+
+    recorder.finishRecordingAsPicture();
+}
+
 namespace {
 
 class MockFilterCanvas : public SkPaintFilterCanvas {
 public:
     MockFilterCanvas(SkCanvas* canvas) : INHERITED(canvas) { }
 
 protected:
     bool onFilter(SkTCopyOnFirstWrite<SkPaint>*, Type) const override { return true; }
 
 private:
@@ skipping 13 matching lines @@
     MockFilterCanvas filterCanvas(&canvas);
     REPORTER_ASSERT(reporter, canvas.getTotalMatrix() == filterCanvas.getTotalMatrix());
     REPORTER_ASSERT(reporter, canvas.getClipBounds(&clip1) == filterCanvas.getClipBounds(&clip2));
     REPORTER_ASSERT(reporter, clip1 == clip2);
 
     filterCanvas.clipRect(SkRect::MakeXYWH(30.5f, 30.7f, 100, 100));
     filterCanvas.scale(0.75f, 0.5f);
     REPORTER_ASSERT(reporter, canvas.getTotalMatrix() == filterCanvas.getTotalMatrix());
     REPORTER_ASSERT(reporter, canvas.getClipBounds(&clip1) == filterCanvas.getClipBounds(&clip2));
     REPORTER_ASSERT(reporter, clip1 == clip2);
+
+    test_updatedepth(reporter);
 }