CL for perf tryjob on linux

third_party/WebKit/Source/platform/graphics/paint/DisplayItemList.h

 // Copyright 2014 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 DisplayItemList_h
 #define DisplayItemList_h
 
 #include "platform/PlatformExport.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/geometry/IntRect.h"
@@ skipping 13 matching lines @@
 namespace blink {
 
 class GraphicsLayer;
 class GraphicsContext;
 
 // kDisplayItemAlignment must be a multiple of alignof(derived display item) for
 // each derived display item; the ideal value is the least common multiple.
 // Currently the limiting factor is TransformtionMatrix (in
 // BeginTransform3DDisplayItem), which requests 16-byte alignment.
 static const size_t kDisplayItemAlignment = WTF_ALIGN_OF(BeginTransform3DDisplayItem);
-static const size_t kInitialDisplayItemsCapacity = 64;
 static const size_t kMaximumDisplayItemSize = sizeof(BeginTransform3DDisplayItem);
+static const size_t kTypicalDisplayItemSize = sizeof(BeginTransform3DDisplayItem);
+// 16 "typically sized items" is the same as this many large items:
+static const size_t kInitialDisplayItemsCapacity = 8 * kTypicalDisplayItemSize / kMaximumDisplayItemSize + 1;
 
 class DisplayItems : public ContiguousContainer<DisplayItem, kDisplayItemAlignment> {
 public:
     DisplayItems(size_t initialSizeBytes)
         : ContiguousContainer(kMaximumDisplayItemSize, initialSizeBytes) {}
 
     DisplayItem& appendByMoving(DisplayItem& item)
     {
 #ifndef NDEBUG
         WTF::String originalDebugString = item.asDebugString();
@@ skipping 205 matching lines @@
     // the duplicated ids are from.
     DisplayItemIndicesByClientMap m_newDisplayItemIndicesByClient;
 #endif
 
     OwnPtr<Vector<String>> m_trackedPaintInvalidationObjects;
 };
 
 } // namespace blink
 
 #endif // DisplayItemList_h