Blink side of changes to enable cache clearing without a flag.

Source/platform/graphics/ContentLayerDelegate.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 35 matching lines @@
     , m_opaque(false)
 {
 }
 
 ContentLayerDelegate::~ContentLayerDelegate()
 {
 }
 
 void ContentLayerDelegate::paintContents(
     SkCanvas* canvas, const WebRect& clip,
-    WebContentLayerClient::GraphicsContextStatus contextStatus)
+    WebContentLayerClient::PaintingControlSetting paintingControl)
 {
     static const unsigned char* annotationsEnabled = 0;
     if (UNLIKELY(!annotationsEnabled))
         annotationsEnabled = EventTracer::getTraceCategoryEnabledFlag(TRACE_DISABLED_BY_DEFAULT("blink.graphics_context_annotations"));
 
-    GraphicsContext context(canvas, m_painter->displayItemList(), contextStatus == WebContentLayerClient::GraphicsContextEnabled ? GraphicsContext::NothingDisabled : GraphicsContext::FullyDisabled);
+    GraphicsContext context(canvas, m_painter->displayItemList(), paintingControl == WebContentLayerClient::PaintDefaultBehavior ? GraphicsContext::NothingDisabled : GraphicsContext::FullyDisabled);

[chrishtr, 2015/02/03 22:05:43]

Don't you want to set FullyDisabled only with DisplayListConstructionDisabled?

[Stephen Chennney, 2015/02/03 22:11:32]

Yes, that makes more sense. We can then get 3 modes with Slimming Paint:
default, cache disabled, and nothing in SkPictures.

     context.setCertainlyOpaque(m_opaque);
     if (*annotationsEnabled)
         context.setAnnotationMode(AnnotateAll);
 
     m_painter->paint(context, clip);
 
     if (DisplayItemList* displayItemList = m_painter->displayItemList())
         displayItemList->endNewPaints();
 }
 
 void ContentLayerDelegate::paintContents(
     WebDisplayItemList* webDisplayItemList, const WebRect& clip,
-    WebContentLayerClient::GraphicsContextStatus contextStatus)
+    WebContentLayerClient::PaintingControlSetting paintingControl)
 {
     // Once Slimming Paint is fully implemented, this method will no longer
     // be needed since Blink will be in charge of creating the display list
     // during the document lifecylcle.
 
+    if (paintingControl == WebContentLayerClient::DisplayListCachingDisabled)
+        m_painter->displayItemList()->invalidateAll();
+
     // Some layers don't yet produce display lists. To handle such layers, we
     // create a canvas backed by an SkPicture, and manually insert this
     // SkPicture into the WebDisplayItemList when the layer's display list is
     // empty.
     SkPictureRecorder recorder;
     RefPtr<SkPicture> picture;
     SkCanvas* canvas = recorder.beginRecording(clip.width, clip.height);
     canvas->save();
     canvas->translate(-clip.x, -clip.y);
     canvas->clipRect(SkRect::MakeXYWH(clip.x, clip.y, clip.width, clip.height));
-    paintContents(canvas, clip, contextStatus);
+    paintContents(canvas, clip, paintingControl);
     canvas->restore();
     picture = adoptRef(recorder.endRecording());
 
     const PaintList& paintList = m_painter->displayItemList()->paintList();
     for (PaintList::const_iterator it = paintList.begin(); it != paintList.end(); ++it)
         (*it)->appendToWebDisplayItemList(webDisplayItemList);
 }
 
 } // namespace blink