Create PaintChunk and begin writing code to build paint chunks.

third_party/WebKit/Source/platform/graphics/paint/SubsequenceRecorder.cpp

 // 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 "config.h"
 #include "platform/graphics/paint/SubsequenceRecorder.h"
 
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/paint/CachedDisplayItem.h"
 #include "platform/graphics/paint/DisplayItemList.h"
 #include "platform/graphics/paint/SubsequenceDisplayItem.h"
 
 namespace blink {
 
 bool SubsequenceRecorder::useCachedSubsequenceIfPossible(GraphicsContext& context, const DisplayItemClientWrapper& client)
 {
     if (!RuntimeEnabledFeatures::slimmingPaintSubsequenceCachingEnabled())
         return false;
 
     ASSERT(context.displayItemList());
 
+    // TODO(jbroman): When SPv2 paint property code can handle it, don't skip

[pdr., 2015/10/01 00:32:48]

I think we should hold off on turning off subsequences for now, since Xianzhu is
still working on them a bit and it'll require updating a bunch of tests.
Instead, lets just rely on your comment in commitNewDisplayItems.

[jbroman, 2015/10/01 18:04:20]

Done.

+    // subsequence recording.
+    if (RuntimeEnabledFeatures::slimmingPaintV2Enabled())
+        return false;
+
     if (context.displayItemList()->displayItemConstructionIsDisabled())
         return false;
 
     if (!context.displayItemList()->clientCacheIsValid(client.displayItemClient()))
         return false;
 
     context.displayItemList()->createAndAppend<CachedDisplayItem>(client, DisplayItem::CachedSubsequence);
 
 #if ENABLE(ASSERT)
     // When under-invalidation checking is enabled, we output CachedSubsequence display item
     // followed by forced painting of the subsequence.
     if (RuntimeEnabledFeatures::slimmingPaintUnderInvalidationCheckingEnabled())
         return false;
 #endif
 
     return true;
 }
 
 SubsequenceRecorder::SubsequenceRecorder(GraphicsContext& context, const DisplayItemClientWrapper& client)
     : m_displayItemList(context.displayItemList())
     , m_client(client)
     , m_beginSubsequenceIndex(0)
 {
     if (!RuntimeEnabledFeatures::slimmingPaintSubsequenceCachingEnabled())
         return;
 
+    // TODO(jbroman): When SPv2 paint property code can handle it, don't skip
+    // subsequence recording.
+    if (RuntimeEnabledFeatures::slimmingPaintV2Enabled())
+        return;
+
     ASSERT(m_displayItemList);
     if (m_displayItemList->displayItemConstructionIsDisabled())
         return;
 
     m_beginSubsequenceIndex = m_displayItemList->newDisplayItems().size();
     m_displayItemList->createAndAppend<BeginSubsequenceDisplayItem>(m_client);
 }
 
 SubsequenceRecorder::~SubsequenceRecorder()
 {
@@ skipping 22 matching lines @@
         return;
 
     if (m_displayItemList->displayItemConstructionIsDisabled())
         return;
 
     ASSERT(m_displayItemList->newDisplayItems()[m_beginSubsequenceIndex].type() == DisplayItem::BeginSubsequence);
     m_displayItemList->newDisplayItems()[m_beginSubsequenceIndex].setSkippedCache();
 }
 
 } // namespace blink