mix-blend-mode implementation for accelerated layers - blink part

public/platform/WebCompositingReasons.h

Index: public/platform/WebCompositingReasons.h
diff --git a/public/platform/WebCompositingReasons.h b/public/platform/WebCompositingReasons.h
index 5eae50719cc336033e4970e1ff0ca31a6af79cae..6d51fd3a2df4771e98fc36cd01b5a4a5a76bf521 100644
--- a/public/platform/WebCompositingReasons.h
+++ b/public/platform/WebCompositingReasons.h
@@ -72,6 +72,7 @@ const uint64_t CompositingReasonLayerForBackground                     = static_
 const uint64_t CompositingReasonLayerForMask                           = static_cast<uint64_t>(1) << 31;
 const uint64_t CompositingReasonOverflowScrollingParent                = static_cast<uint64_t>(1) << 32;
 const uint64_t CompositingReasonOutOfFlowClipping                      = static_cast<uint64_t>(1) << 33;
+const uint64_t CompositingReasonIsolateCompositedDescendants           = static_cast<uint64_t>(1) << 35;
 
 typedef uint64_t WebCompositingReasons;