CSS Blending: Mix-blend-mode shouldn't force the creation of a composited layer.

cc/layers/compositing_reasons.h

 // Copyright 2013 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_LAYERS_COMPOSITING_REASONS_H_
 #define CC_LAYERS_COMPOSITING_REASONS_H_
 
 #include "base/port.h"
 
 namespace cc {
 
 // This is a clone of CompositingReasons and WebCompositingReasons from Blink.
 const uint64 kCompositingReasonUnknown = 0;
 const uint64 kCompositingReason3DTransform = GG_UINT64_C(1) << 0;
 const uint64 kCompositingReasonVideo = GG_UINT64_C(1) << 1;
 const uint64 kCompositingReasonCanvas = GG_UINT64_C(1) << 2;
 const uint64 kCompositingReasonPlugin = GG_UINT64_C(1) << 3;
 const uint64 kCompositingReasonIFrame = GG_UINT64_C(1) << 4;
 const uint64 kCompositingReasonBackfaceVisibilityHidden = GG_UINT64_C(1) << 5;
 const uint64 kCompositingReasonAnimation = GG_UINT64_C(1) << 6;
 const uint64 kCompositingReasonFilters = GG_UINT64_C(1) << 7;
 const uint64 kCompositingReasonPositionFixed = GG_UINT64_C(1) << 8;
 const uint64 kCompositingReasonPositionSticky = GG_UINT64_C(1) << 9;
 const uint64 kCompositingReasonOverflowScrollingTouch = GG_UINT64_C(1) << 10;
-const uint64 kCompositingReasonBlending = GG_UINT64_C(1) << 11;
 const uint64 kCompositingReasonAssumedOverlap = GG_UINT64_C(1) << 12;
 const uint64 kCompositingReasonOverlap = GG_UINT64_C(1) << 13;
 const uint64 kCompositingReasonNegativeZIndexChildren = GG_UINT64_C(1) << 14;
 const uint64 kCompositingReasonTransformWithCompositedDescendants =
     GG_UINT64_C(1) << 15;
 const uint64 kCompositingReasonOpacityWithCompositedDescendants =
     GG_UINT64_C(1) << 16;
 const uint64 kCompositingReasonMaskWithCompositedDescendants =
     GG_UINT64_C(1) << 17;
 const uint64 kCompositingReasonReflectionWithCompositedDescendants =
@@ skipping 17 matching lines @@
 const uint64 kCompositingReasonLayerForBackground = GG_UINT64_C(1) << 30;
 const uint64 kCompositingReasonLayerForMask = GG_UINT64_C(1) << 31;
 const uint64 kCompositingReasonOverflowScrollingParent = GG_UINT64_C(1) << 32;
 const uint64 kCompositingReasonOutOfFlowClipping = GG_UINT64_C(1) << 33;
 
 typedef uint64 CompositingReasons;
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_COMPOSITING_REASONS_H_