cc: Delete SidecarListContainer.

Using its features to support Blink display item lists is not longer part of the
plan of record.

BUG=529859
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1319973013

Cr-Commit-Position: refs/heads/master@{#348051}

10 files changed, 5 insertions, 322 deletions

diff --git a/cc/BUILD.gn b/cc/BUILD.gn
index 1f9fe77..6eab5c8 100644
--- a/cc/BUILD.gn
+++ b/cc/BUILD.gn
@@ -729,7 +729,6 @@ test("cc_unittests") {
     "base/region_unittest.cc",
     "base/rolling_time_delta_history_unittest.cc",
     "base/scoped_ptr_vector_unittest.cc",
-    "base/sidecar_list_container_unittest.cc",
     "base/simple_enclosed_region_unittest.cc",
     "base/tiling_data_unittest.cc",
     "base/unique_notifier_unittest.cc",
diff --git a/cc/base/BUILD.gn b/cc/base/BUILD.gn
index 98a5d4a..d02b900 100644
--- a/cc/base/BUILD.gn
+++ b/cc/base/BUILD.gn
@@ -25,7 +25,6 @@ source_set("base") {
     "scoped_ptr_algorithm.h",
     "scoped_ptr_deque.h",
     "scoped_ptr_vector.h",
-    "sidecar_list_container.h",
     "simple_enclosed_region.cc",
     "simple_enclosed_region.h",
     "switches.cc",
diff --git a/cc/base/sidecar_list_container.h b/cc/base/sidecar_list_container.h
deleted file mode 100644
index 5135ab1..0000000
--- a/cc/base/sidecar_list_container.h
+++ /dev/null
@@ -1,97 +0,0 @@
-// Copyright 2015 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.
-
-#ifndef CC_BASE_SIDECAR_LIST_CONTAINER_H_
-#define CC_BASE_SIDECAR_LIST_CONTAINER_H_
-
-#include "base/logging.h"
-#include "cc/base/list_container.h"
-
-namespace cc {
-
-// This is a container, based on ListContainer, which allocates space in a
-// contiguous block for objects subclassing BaseElementType, as well as an
-// additional "sidecar" of opaque type.
-//
-// It takes a pointer to a function for tearing down sidecar objects, which must
-// free any resources held by it as its memory will be deallocated by the
-// container afterwards. When an element is constructed, callers are expected to
-// immediately construct the sidecar as well (such that the sidecar destroyer
-// will run safely and successfully).
-//
-// TODO(jbroman): It would be nice to be clear about the memory alignment
-// constraints here, but that probably requires closer inspection of
-// ListContainer first.
-template <class BaseElementType>
-class SidecarListContainer {
- public:
-  using SidecarDestroyer = void (*)(void* sidecar);
-  using Iterator = typename ListContainer<BaseElementType>::Iterator;
-  using ConstIterator = typename ListContainer<BaseElementType>::ConstIterator;
-  using ReverseIterator =
-      typename ListContainer<BaseElementType>::ReverseIterator;
-  using ConstReverseIterator =
-      typename ListContainer<BaseElementType>::ConstReverseIterator;
-
-  explicit SidecarListContainer(size_t max_size_for_derived_class,
-                                size_t max_size_for_sidecar,
-                                size_t num_of_elements_to_reserve_for,
-                                SidecarDestroyer destroyer)
-      : list_(max_size_for_derived_class + max_size_for_sidecar,
-              num_of_elements_to_reserve_for),
-        destroyer_(destroyer),
-        sidecar_offset_(max_size_for_derived_class) {}
-  ~SidecarListContainer() { DestroyAllSidecars(); }
-
-  // Forward most of the reading logic to ListContainer.
-  bool empty() const { return list_.empty(); }
-  size_t size() const { return list_.size(); }
-  size_t GetCapacityInBytes() const { return list_.GetCapacityInBytes(); }
-  ConstIterator begin() const { return list_.begin(); }
-  ConstIterator end() const { return list_.end(); }
-
-  template <typename DerivedElementType>
-  DerivedElementType* AllocateAndConstruct() {
-    return list_.template AllocateAndConstruct<DerivedElementType>();
-  }
-  template <typename DerivedElementType>
-  DerivedElementType* AllocateAndCopyFrom(const DerivedElementType* source) {
-    return list_.template AllocateAndCopyFrom<DerivedElementType>(source);
-  }
-
-  void clear() {
-    DestroyAllSidecars();
-    list_.clear();
-  }
-
-  void RemoveLast() {
-    destroyer_(GetSidecar(*list_.rbegin()));
-    list_.RemoveLast();
-  }
-
-  // This permits a client to exchange a pointer to an element to a pointer to
-  // its corresponding sidecar.
-  void* GetSidecar(BaseElementType* element) {
-    DCHECK_GT(sidecar_offset_, 0u);
-    return reinterpret_cast<char*>(element) + sidecar_offset_;
-  }
-  const void* GetSidecar(const BaseElementType* element) {
-    DCHECK_GT(sidecar_offset_, 0u);
-    return reinterpret_cast<const char*>(element) + sidecar_offset_;
-  }
-
- private:
-  void DestroyAllSidecars() {
-    for (auto* element : list_)
-      destroyer_(GetSidecar(element));
-  }
-
-  ListContainer<BaseElementType> list_;
-  SidecarDestroyer destroyer_;
-  size_t sidecar_offset_;
-};
-
-}  // namespace cc
-
-#endif  // CC_BASE_SIDECAR_LIST_CONTAINER_H_
diff --git a/cc/base/sidecar_list_container_unittest.cc b/cc/base/sidecar_list_container_unittest.cc
deleted file mode 100644
index 0012014..0000000
--- a/cc/base/sidecar_list_container_unittest.cc
+++ /dev/null
@@ -1,198 +0,0 @@
-// Copyright 2015 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/base/sidecar_list_container.h"
-
-#include <algorithm>
-
-#include "base/logging.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace cc {
-namespace {
-
-const size_t kNumInitiallyReservedElements = 2;
-const size_t kNumElementsForTest = 100;
-
-class DestructionNotifier {
- public:
-  DestructionNotifier() : flag_(nullptr) {}
-  explicit DestructionNotifier(bool* flag) { set_flag(flag); }
-  ~DestructionNotifier() {
-    if (flag_)
-      *flag_ = true;
-  }
-  void set_flag(bool* flag) {
-    if (flag)
-      DCHECK(!*flag);
-    flag_ = flag;
-  }
-
- private:
-  bool* flag_;
-};
-
-class TestElement {
- public:
-  TestElement() {}
-  virtual ~TestElement() {}
-  void set_destruction_flag(bool* flag) { notifier_.set_flag(flag); }
-
- private:
-  DestructionNotifier notifier_;
-};
-
-class DerivedTestElement : public TestElement {
- public:
-  int additional_field = 0;
-};
-
-class TestSidecar {
- public:
-  TestSidecar() {}
-  explicit TestSidecar(bool* destruction_flag) : notifier_(destruction_flag) {}
-
-  static void Destroy(void* sidecar) {
-    static_cast<TestSidecar*>(sidecar)->~TestSidecar();
-  }
-
- protected:
-  virtual ~TestSidecar() {}
-
- private:
-  DestructionNotifier notifier_;
-};
-
-class DerivedTestSidecar : public TestSidecar {
- public:
-  DerivedTestSidecar() {}
-  explicit DerivedTestSidecar(bool* destruction_flag)
-      : TestSidecar(destruction_flag) {}
-  int additional_field = 0;
-
- private:
-  ~DerivedTestSidecar() override {}
-};
-
-class TestContainer : public SidecarListContainer<TestElement> {
- public:
-  TestContainer()
-      : SidecarListContainer(
-            std::max(sizeof(TestElement), sizeof(DerivedTestElement)),
-            std::max(sizeof(TestSidecar), sizeof(DerivedTestSidecar)),
-            kNumInitiallyReservedElements,
-            &TestSidecar::Destroy) {}
-};
-
-TEST(SidecarListContainerTest, Destructor) {
-  bool element_destroyed = false;
-  bool sidecar_destroyed = false;
-
-  {
-    TestContainer container;
-
-    TestElement* element = container.AllocateAndConstruct<TestElement>();
-    TestSidecar* sidecar =
-        new (container.GetSidecar(element)) TestSidecar(&sidecar_destroyed);
-    element->set_destruction_flag(&element_destroyed);
-
-    // They shouldn't be destroyed yet. And they shouldn't overlap in memory.
-    ASSERT_FALSE(element_destroyed);
-    ASSERT_FALSE(sidecar_destroyed);
-    ASSERT_GE(reinterpret_cast<char*>(sidecar),
-              reinterpret_cast<char*>(element) + sizeof(TestElement));
-  }
-
-  // They should, however, be destroyed when going out of scope.
-  ASSERT_TRUE(element_destroyed);
-  ASSERT_TRUE(sidecar_destroyed);
-}
-
-TEST(SidecarListContainerTest, Clear) {
-  bool element_destroyed = false;
-  bool sidecar_destroyed = false;
-
-  TestContainer container;
-
-  TestElement* element = container.AllocateAndConstruct<TestElement>();
-  new (container.GetSidecar(element)) TestSidecar(&sidecar_destroyed);
-  element->set_destruction_flag(&element_destroyed);
-
-  // They shouldn't be destroyed yet.
-  ASSERT_FALSE(element_destroyed);
-  ASSERT_FALSE(sidecar_destroyed);
-
-  // They should, however, be destroyed after clearing.
-  container.clear();
-  EXPECT_TRUE(element_destroyed);
-  EXPECT_TRUE(sidecar_destroyed);
-}
-
-TEST(SidecarListContainerTest, DerivedTypes) {
-  bool element_destroyed = false;
-  bool sidecar_destroyed = false;
-
-  {
-    TestContainer container;
-
-    DerivedTestElement* element =
-        container.AllocateAndConstruct<DerivedTestElement>();
-    DerivedTestSidecar* sidecar = new (container.GetSidecar(element))
-        DerivedTestSidecar(&sidecar_destroyed);
-    element->set_destruction_flag(&element_destroyed);
-    element->additional_field = 12;
-    sidecar->additional_field = 13;
-
-    // They shouldn't be destroyed yet.
-    ASSERT_FALSE(element_destroyed);
-    ASSERT_FALSE(sidecar_destroyed);
-  }
-
-  // They should, however, be destroyed when going out of scope.
-  EXPECT_TRUE(element_destroyed);
-  EXPECT_TRUE(sidecar_destroyed);
-}
-
-TEST(SidecarListContainerTest, AddingAndRemovingElements) {
-  TestContainer container;
-  EXPECT_TRUE(container.empty());
-  EXPECT_EQ(0u, container.size());
-  EXPECT_EQ(container.end(), container.begin());
-
-  for (size_t i = 1; i <= kNumElementsForTest; i++) {
-    TestElement* element = container.AllocateAndConstruct<TestElement>();
-    new (container.GetSidecar(element)) TestSidecar();
-
-    ASSERT_FALSE(container.empty());
-    ASSERT_EQ(i, container.size());
-    ASSERT_NE(container.end(), container.begin());
-  }
-
-  size_t num_elements = 0;
-  for (const auto* element : container) {
-    (void)element;
-    num_elements++;
-  }
-  EXPECT_EQ(kNumElementsForTest, num_elements);
-
-  container.clear();
-  EXPECT_TRUE(container.empty());
-  EXPECT_EQ(0u, container.size());
-  EXPECT_EQ(container.end(), container.begin());
-}
-
-TEST(SidecarListContainerTest, RemoveLast) {
-  // We need only ensure that the sidecar is also destroyed on RemoveLast.
-  // The rest is logic already present in ListContainer.
-  bool sidecar_destroyed = false;
-  TestContainer container;
-  TestElement* element = container.AllocateAndConstruct<TestElement>();
-  new (container.GetSidecar(element)) TestSidecar(&sidecar_destroyed);
-  ASSERT_FALSE(sidecar_destroyed);
-  container.RemoveLast();
-  ASSERT_TRUE(sidecar_destroyed);
-}
-
-}  // namespace
-}  // namespace cc
diff --git a/cc/cc.gyp b/cc/cc.gyp
index c0fb72f..df9f9bd 100644
--- a/cc/cc.gyp
+++ b/cc/cc.gyp
@@ -92,7 +92,6 @@
         'base/scoped_ptr_algorithm.h',
         'base/scoped_ptr_deque.h',
         'base/scoped_ptr_vector.h',
-        'base/sidecar_list_container.h',
         'base/simple_enclosed_region.cc',
         'base/simple_enclosed_region.h',
         'base/switches.cc',
diff --git a/cc/cc_tests.gyp b/cc/cc_tests.gyp
index c824da0..deb7d32 100644
--- a/cc/cc_tests.gyp
+++ b/cc/cc_tests.gyp
@@ -25,7 +25,6 @@
       'base/region_unittest.cc',
       'base/rolling_time_delta_history_unittest.cc',
       'base/scoped_ptr_vector_unittest.cc',
-      'base/sidecar_list_container_unittest.cc',
       'base/simple_enclosed_region_unittest.cc',
       'base/tiling_data_unittest.cc',
       'base/unique_notifier_unittest.cc',
diff --git a/cc/playback/display_item_list.cc b/cc/playback/display_item_list.cc
index 6959c69..73e8762 100644
--- a/cc/playback/display_item_list.cc
+++ b/cc/playback/display_item_list.cc
@@ -43,10 +43,7 @@ const int kDefaultNumDisplayItemsToReserve = 100;
 DisplayItemList::DisplayItemList(gfx::Rect layer_rect,
                                  const DisplayItemListSettings& settings,
                                  bool retain_individual_display_items)
-    : items_(LargestDisplayItemSize(),
-             settings.max_sidecar_size,
-             kDefaultNumDisplayItemsToReserve,
-             settings.sidecar_destroyer),
+    : items_(LargestDisplayItemSize(), kDefaultNumDisplayItemsToReserve),
       use_cached_picture_(settings.use_cached_picture),
       retain_individual_display_items_(retain_individual_display_items),
       layer_rect_(layer_rect),
@@ -305,8 +302,4 @@ void DisplayItemList::GatherDiscardableImages(const gfx::Size& grid_cell_size) {
   images_->GatherImagesFromPicture(picture_.get(), layer_rect_);
 }
 
-void* DisplayItemList::GetSidecar(DisplayItem* display_item) {
-  return items_.GetSidecar(display_item);
-}
-
 }  // namespace cc
diff --git a/cc/playback/display_item_list.h b/cc/playback/display_item_list.h
index 92a423e..e85fe10 100644
--- a/cc/playback/display_item_list.h
+++ b/cc/playback/display_item_list.h
@@ -10,8 +10,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/base/cc_export.h"
-#include "cc/base/scoped_ptr_vector.h"
-#include "cc/base/sidecar_list_container.h"
+#include "cc/base/list_container.h"
 #include "cc/playback/discardable_image_map.h"
 #include "cc/playback/display_item.h"
 #include "skia/ext/refptr.h"
@@ -32,7 +31,7 @@ class CC_EXPORT DisplayItemList
       const DisplayItemListSettings& settings);
 
   // Creates a display item list with the given cull rect (if picture caching
-  // is used). The resulting display list will not support sidecar data.
+  // is used).
   static scoped_refptr<DisplayItemList> Create(gfx::Rect layer_rect,
                                                bool use_cached_picture);
 
@@ -82,9 +81,6 @@ class CC_EXPORT DisplayItemList
 
   void GatherDiscardableImages(const gfx::Size& grid_cell_size);
 
-  // Finds the sidecar for a display item in this list.
-  void* GetSidecar(DisplayItem* display_item);
-
  private:
   DisplayItemList(gfx::Rect layer_rect,
                   const DisplayItemListSettings& display_list_settings,
@@ -104,7 +100,7 @@ class CC_EXPORT DisplayItemList
   bool ProcessAppendedItemsCalled() const { return true; }
 #endif
 
-  SidecarListContainer<DisplayItem> items_;
+  ListContainer<DisplayItem> items_;
   skia::RefPtr<SkPicture> picture_;
 
   scoped_ptr<SkPictureRecorder> recorder_;
diff --git a/cc/playback/display_item_list_settings.cc b/cc/playback/display_item_list_settings.cc
index e471d7e..c71d9ee 100644
--- a/cc/playback/display_item_list_settings.cc
+++ b/cc/playback/display_item_list_settings.cc
@@ -7,10 +7,7 @@
 namespace cc {
 
 DisplayItemListSettings::DisplayItemListSettings()
-    : use_cached_picture(false),
-      max_sidecar_size(0),
-      sidecar_destroyer([](void* sidecar) {}) {
-}
+    : use_cached_picture(false) {}
 
 DisplayItemListSettings::~DisplayItemListSettings() {
 }
diff --git a/cc/playback/display_item_list_settings.h b/cc/playback/display_item_list_settings.h
index 277a2ea..85fe8db 100644
--- a/cc/playback/display_item_list_settings.h
+++ b/cc/playback/display_item_list_settings.h
@@ -18,10 +18,6 @@ class CC_EXPORT DisplayItemListSettings {
 
   // If set, a picture will be cached inside the DisplayItemList.
   bool use_cached_picture;
-
-  // Settings that control sidecar data.
-  size_t max_sidecar_size;
-  void (*sidecar_destroyer)(void* sidecar);
 };
 
 }  // namespace cc