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();
 }
 
+class SkTestCanvas : public SkCanvas {
+public:
+    void testUpdateDepth(skiatest::Reporter* reporter) {
+        // set some depths (with picture enabled), then check them as they get set
+
+        REPORTER_ASSERT(reporter, this->getZ() == 0);
+        this->translateZ(-10);
+        REPORTER_ASSERT(reporter, this->getZ() == -10);
+
+        this->save();
+        this->translateZ(20);
+        REPORTER_ASSERT(reporter, this->getZ() == 10);
+
+        this->restore();
+        REPORTER_ASSERT(reporter, this->getZ() == -10);
+
+        this->translateZ(13.14f);
+        REPORTER_ASSERT(reporter, SkScalarNearlyEqual(this->getZ(),3.14f));
+    }
+};
+
 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);
+
+    SkTestCanvas* tCanvas;
+
+    tCanvas = (SkTestCanvas*) new SkCanvas(100,100);
+    tCanvas->testUpdateDepth(reporter);
 }