Add deprecation message for -webkit-background-composite

third_party/WebKit/Source/core/page/Page.h

Index: third_party/WebKit/Source/core/page/Page.h
diff --git a/third_party/WebKit/Source/core/page/Page.h b/third_party/WebKit/Source/core/page/Page.h
index 4296db8e76c39e19e98ebabb3be2caf0994d3764..23facc00e7e91d88e9917eb395c07c0790192e02 100644
--- a/third_party/WebKit/Source/core/page/Page.h
+++ b/third_party/WebKit/Source/core/page/Page.h
@@ -23,6 +23,7 @@
 
 #include "core/CoreExport.h"
 #include "core/dom/ViewportDescription.h"
+#include "core/frame/Deprecation.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/OriginsUsingFeatures.h"
 #include "core/frame/SettingsDelegate.h"
@@ -163,6 +164,7 @@ public:
     Settings& settings() const { return *m_settings; }
 
     UseCounter& useCounter() { return m_useCounter; }
+    Deprecation& deprecation() { return m_deprecation; }
     OriginsUsingFeatures& originsUsingFeatures() { return m_originsUsingFeatures; }
 
     void setTabKeyCyclesThroughElements(bool b) { m_tabKeyCyclesThroughElements = b; }
@@ -267,6 +269,7 @@ private:
     OwnPtrWillBeMember<ValidationMessageClient> m_validationMessageClient;
 
     UseCounter m_useCounter;
+    Deprecation m_deprecation;
     OriginsUsingFeatures m_originsUsingFeatures;
 
     bool m_openedByDOM;