Remove Layer/LayerImpl's FixedContainerSizeDelta

cc/trees/layer_tree_host_impl_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_impl.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <cmath>
@@ skipping 4407 matching lines @@
     ASSERT_EQ(gfx::Size(50, 100), inner_container->bounds());
     ASSERT_EQ(gfx::Size(50, 100), outer_container->bounds());
     EXPECT_EQ(gfx::SizeF(50, 100), active_tree->ScrollableSize());
     EXPECT_EQ(gfx::SizeF(50, 50), content->BoundsForScrolling());
   }
 
   host_impl_->browser_controls_manager()->ScrollEnd();
   host_impl_->ScrollEnd(EndState().get());
 }
 
+namespace {
+
+gfx::Vector2dF FixedContainerSizeDelta(LayerImpl* scroll_layer) {
+  auto* layer_tree_impl = scroll_layer->layer_tree_impl();
+  auto* property_trees = layer_tree_impl->property_trees();
+  if (auto* inner = layer_tree_impl->InnerViewportContainerLayer()) {
+    if (inner->element_id() == scroll_layer->scroll_clip_layer()->element_id())
+      return property_trees->inner_viewport_container_bounds_delta();
+  }
+  if (auto* outer = layer_tree_impl->OuterViewportContainerLayer()) {
+    if (outer->element_id() == scroll_layer->scroll_clip_layer()->element_id())
+      return property_trees->outer_viewport_container_bounds_delta();
+  }
+
+  return gfx::Vector2dF();
+}
+
+};  // namespace

[enne (OOO), 2017/04/25 00:52:20]

s/;//

[pdr., 2017/04/26 21:29:01]

Done, kinda. And more!

+
 TEST_F(LayerTreeHostImplBrowserControlsTest,
        ScrollBrowserControlsByFractionalAmount) {
   SetupBrowserControlsAndScrollLayerWithVirtualViewport(
       gfx::Size(10, 10), gfx::Size(10, 10), gfx::Size(10, 10));
   DrawFrame();
 
   EXPECT_EQ(InputHandler::SCROLL_ON_IMPL_THREAD,
             host_impl_
                 ->ScrollBegin(BeginState(gfx::Point()).get(),
                               InputHandler::TOUCHSCREEN)
                 .thread);
 
   // Make the test scroll delta a fractional amount, to verify that the
   // fixed container size delta is (1) non-zero, and (2) fractional, and
   // (3) matches the movement of the browser controls.
   gfx::Vector2dF top_controls_scroll_delta(0.f, 5.25f);
   host_impl_->browser_controls_manager()->ScrollBegin();
   host_impl_->browser_controls_manager()->ScrollBy(top_controls_scroll_delta);
   host_impl_->browser_controls_manager()->ScrollEnd();
 
   LayerImpl* inner_viewport_scroll_layer =
       host_impl_->active_tree()->InnerViewportScrollLayer();
   DCHECK(inner_viewport_scroll_layer);
   host_impl_->ScrollEnd(EndState().get());
   EXPECT_FLOAT_EQ(top_controls_scroll_delta.y(),
-                  inner_viewport_scroll_layer->FixedContainerSizeDelta().y());
+                  FixedContainerSizeDelta(inner_viewport_scroll_layer).y());

[enne (OOO), 2017/04/25 00:52:20]

Can you remove the helper and just say
property_trees->inner_viewport_container_bounds_delta() here (and something
similar elsewhere)?

Are the element ids ever different, or can you just EXPECT_EQ them as well
(possibly in the setup)?

[pdr., 2017/04/26 21:29:01]

This is a real good idea. I was focused on the goal of removing
scroll_clip_layer_id_ and missed the forest for the trees.

Latest patch fully removes FixedContainerSizeDelta and makes all of this code
much simpler.

 }
 
 // In this test, the outer viewport is initially unscrollable. We test that a
 // scroll initiated on the inner viewport, causing the browser controls to show
 // and thus making the outer viewport scrollable, still scrolls the outer
 // viewport.
 TEST_F(LayerTreeHostImplBrowserControlsTest,
        BrowserControlsOuterViewportBecomesScrollable) {
   SetupBrowserControlsAndScrollLayerWithVirtualViewport(
       gfx::Size(10, 50), gfx::Size(10, 50), gfx::Size(10, 100));
@@ skipping 101 matching lines @@
                 .thread);
 
   // Scroll down, the browser controls hiding should expand the viewport size so
   // the delta should be equal to the scroll distance.
   gfx::Vector2dF top_controls_scroll_delta(0.f, 20.f);
   host_impl_->browser_controls_manager()->ScrollBegin();
   host_impl_->browser_controls_manager()->ScrollBy(top_controls_scroll_delta);
   EXPECT_FLOAT_EQ(top_controls_height_ - top_controls_scroll_delta.y(),
                   host_impl_->browser_controls_manager()->ContentTopOffset());
   EXPECT_FLOAT_EQ(top_controls_scroll_delta.y(),
-                  outer_viewport_scroll_layer->FixedContainerSizeDelta().y());
+                  FixedContainerSizeDelta(outer_viewport_scroll_layer).y());
   host_impl_->ScrollEnd(EndState().get());
 
   // Scroll past the maximum extent. The delta shouldn't be greater than the
   // browser controls height.
   host_impl_->browser_controls_manager()->ScrollBegin();
   host_impl_->browser_controls_manager()->ScrollBy(top_controls_scroll_delta);
   host_impl_->browser_controls_manager()->ScrollBy(top_controls_scroll_delta);
   host_impl_->browser_controls_manager()->ScrollBy(top_controls_scroll_delta);
   EXPECT_EQ(0.f, host_impl_->browser_controls_manager()->ContentTopOffset());
   EXPECT_VECTOR_EQ(gfx::Vector2dF(0, top_controls_height_),
-                   outer_viewport_scroll_layer->FixedContainerSizeDelta());
+                   FixedContainerSizeDelta(outer_viewport_scroll_layer));
   host_impl_->ScrollEnd(EndState().get());
 
   // Scroll in the direction to make the browser controls show.
   host_impl_->browser_controls_manager()->ScrollBegin();
   host_impl_->browser_controls_manager()->ScrollBy(-top_controls_scroll_delta);
   EXPECT_EQ(top_controls_scroll_delta.y(),
             host_impl_->browser_controls_manager()->ContentTopOffset());
   EXPECT_VECTOR_EQ(
       gfx::Vector2dF(0, top_controls_height_ - top_controls_scroll_delta.y()),
-      outer_viewport_scroll_layer->FixedContainerSizeDelta());
+      FixedContainerSizeDelta(outer_viewport_scroll_layer));
   host_impl_->browser_controls_manager()->ScrollEnd();
 }
 
 // Push a browser controls ratio from the main thread that we didn't send as a
 // delta and make sure that the ratio is clamped to the [0, 1] range.
 TEST_F(LayerTreeHostImplBrowserControlsTest, BrowserControlsPushUnsentRatio) {
   SetupBrowserControlsAndScrollLayerWithVirtualViewport(
       gfx::Size(10, 50), gfx::Size(10, 50), gfx::Size(10, 100));
   DrawFrame();
 
@@ skipping 7773 matching lines @@
     else
       EXPECT_FALSE(tile->HasRasterTask());
   }
   Region expected_invalidation(
       raster_source->GetRectForImage(checkerable_image->uniqueID()));
   EXPECT_EQ(expected_invalidation, *(root->GetPendingInvalidation()));
 }
 
 }  // namespace
 }  // namespace cc