Reland Don't assert rect mapping result if impossible

third_party/WebKit/Source/core/layout/PaintInvalidationState.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 PaintInvalidationState_h
 #define PaintInvalidationState_h
 
 #include "core/CoreExport.h"
 #include "platform/geometry/LayoutRect.h"
 #include "platform/transforms/AffineTransform.h"
@@ skipping 124 matching lines @@
     // with |m_paintOffset| yields the "final" offset.
     AffineTransform m_svgTransform;
 
     Vector<LayoutObject*>& m_pendingDelayedPaintInvalidations;
 
     PaintLayer& m_enclosingSelfPaintingLayer;
 
 #if ENABLE(ASSERT)
     bool m_didUpdateForChildren;
 #endif
+
+#if ENABLE(ASSERT) && !defined(NDEBUG)
+// #define CHECK_FAST_PATH_SLOW_PATH_EQUALITY
+#endif
+
+#ifdef CHECK_FAST_PATH_SLOW_PATH_EQUALITY
+    void assertFastPathAndSlowPathRectsEqual(const LayoutRect& fastPathRect, const LayoutRect& slowPathRect) const;
+    bool m_canCheckFastPathSlowPathEquality;
+#endif
 };
 
 } // namespace blink
 
 #endif // PaintInvalidationState_h