Rename OS(DARWIN) to OS(MACOSX).

Source/core/page/Settings.cpp

Index: Source/core/page/Settings.cpp
diff --git a/Source/core/page/Settings.cpp b/Source/core/page/Settings.cpp
index 148aacf265cbacdc8fa9ad2dfc5a56d18da0dd8c..08eec31ecdd10799e8c14156680d80b7b9dfd20a 100644
--- a/Source/core/page/Settings.cpp
+++ b/Source/core/page/Settings.cpp
@@ -88,7 +88,7 @@ bool Settings::gUsesOverlayScrollbars = false;
 static EditingBehaviorType editingBehaviorTypeForPlatform()
 {
     return
-#if OS(DARWIN)
+#if OS(MACOSX)
     EditingMacBehavior
 #elif OS(WINDOWS)
     EditingWindowsBehavior
@@ -104,7 +104,7 @@ static EditingBehaviorType editingBehaviorTypeForPlatform()
 }
 
 static const bool defaultUnifiedTextCheckerEnabled = false;
-#if OS(DARWIN)
+#if OS(MACOSX)
 static const bool defaultSmartInsertDeleteEnabled = true;
 #else
 static const bool defaultSmartInsertDeleteEnabled = false;