cc: Consider scroll offset in CalcDrawProperties

cc/trees/layer_tree_host_common_unittest.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/layer_tree_host_common.h"
 
 #include "cc/animation/layer_animation_controller.h"
 #include "cc/base/math_util.h"
 #include "cc/layers/content_layer.h"
 #include "cc/layers/content_layer_client.h"
@@ skipping 376 matching lines @@
                                gfx::PointF(0.5f, 0.f),
                                gfx::PointF(0.f, 1.2f),
                                gfx::Size(10, 12),
                                false);
   ExecuteCalculateDrawProperties(root.get());
   EXPECT_TRANSFORMATION_MATRIX_EQ(expected_result, layer->draw_transform());
   EXPECT_TRANSFORMATION_MATRIX_EQ(expected_result,
                                   layer->screen_space_transform());
 }
 
 TEST(LayerTreeHostCommonTest, TransformsAboutScrollOffset) {

[danakj, 2013/07/08 21:53:42]

Maybe this should be named DoesNotTransformAbountScrollPositionOrOffset now?

[enne (OOO), 2013/07/08 22:03:46]

Only the inputs to this test have changed, in parallel with the reverted code in
WebLayerImpl.  This test hasn't changed what it's testing, so I'm confused about
what you're suggesting to rename it to.

[danakj, 2013/07/09 01:52:45]

Mmm.. right, the scroll offset/delta are still used directly, just not included
in the layer's position anymore. Nevermind!

   const gfx::Vector2d kScrollOffset(50, 100);
   const gfx::Vector2dF kScrollDelta(2.34f, 5.67f);
   const gfx::PointF kScrollLayerPosition(-kScrollOffset.x(),
                                          -kScrollOffset.y());
   const float kPageScale = 0.888f;
   const float kDeviceScale = 1.666f;
 
   FakeImplProxy proxy;
   FakeLayerTreeHostImpl host_impl(&proxy);
 
@@ skipping 11 matching lines @@
                                gfx::Size(500, 500),
                                false);
 
   scoped_ptr<LayerImpl> scroll_layerScopedPtr(
       LayerImpl::Create(host_impl.active_tree(), 2));
   LayerImpl* scroll_layer = scroll_layerScopedPtr.get();
   SetLayerPropertiesForTesting(scroll_layer,
                                identity_matrix,
                                identity_matrix,
                                gfx::PointF(),
-                               kScrollLayerPosition,
+                               gfx::PointF(),
                                gfx::Size(10, 20),
                                false);
   scroll_layer->SetScrollable(true);
   scroll_layer->SetScrollOffset(kScrollOffset);
   scroll_layer->SetScrollDelta(kScrollDelta);
   gfx::Transform impl_transform;
   scroll_layer->AddChild(sublayer_scoped_ptr.Pass());
 
   scoped_ptr<LayerImpl> root(LayerImpl::Create(host_impl.active_tree(), 3));
   SetLayerPropertiesForTesting(root.get(),
@@ skipping 18 matching lines @@
                                   sublayer->screen_space_transform());
 
   gfx::Transform arbitrary_translate;
   const float kTranslateX = 10.6f;
   const float kTranslateY = 20.6f;
   arbitrary_translate.Translate(kTranslateX, kTranslateY);
   SetLayerPropertiesForTesting(scroll_layer,
                                arbitrary_translate,
                                identity_matrix,
                                gfx::PointF(),
-                               kScrollLayerPosition,
+                               gfx::PointF(),
                                gfx::Size(10, 20),
                                false);
   ExecuteCalculateDrawProperties(
       root.get(), kDeviceScale, kPageScale, scroll_layer);
   expected_transform.MakeIdentity();
   expected_transform.Translate(
       MathUtil::Round(kTranslateX * kPageScale * kDeviceScale +
                       sub_layer_screen_position.x()),
       MathUtil::Round(kTranslateY * kPageScale * kDeviceScale +
                       sub_layer_screen_position.y()));
@@ skipping 7852 matching lines @@
   EXPECT_EQ(root->id(), render_surface_layer_list[0]->id());
 
   // The root render surface should only have 1 contributing layer, since the
   // other layers are empty/clipped away.
   ASSERT_EQ(1u, root->render_surface()->layer_list().size());
   EXPECT_EQ(root->id(), root->render_surface()->layer_list()[0]->id());
 }
 
 }  // namespace
 }  // namespace cc