Consolidate SDK forwards in sdk_forward_declarations.h.

chrome/browser/ui/cocoa/nsview_additions.mm

Index: chrome/browser/ui/cocoa/nsview_additions.mm
diff --git a/chrome/browser/ui/cocoa/nsview_additions.mm b/chrome/browser/ui/cocoa/nsview_additions.mm
index 6d8ed4b10b3f4dd83d11fff6d1290032b6b56432..38e6e94b1dd63e42d47a67940a1f21d15bd54c54 100644
--- a/chrome/browser/ui/cocoa/nsview_additions.mm
+++ b/chrome/browser/ui/cocoa/nsview_additions.mm
@@ -4,6 +4,7 @@
 
 #include "base/command_line.h"
 #include "base/mac/mac_util.h"
+#include "base/mac/sdk_forward_declarations.h"
 #import "chrome/browser/ui/cocoa/nsview_additions.h"
 #include "chrome/common/chrome_switches.h"
 #include "ui/base/ui_base_switches.h"
@@ -11,27 +12,6 @@
 
 #include "base/logging.h"
 
-#if !defined(MAC_OS_X_VERSION_10_7) || \
-    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7
-
-@interface NSView (LionAPI)
-- (NSSize)convertSizeFromBacking:(NSSize)size;
-@end
-
-#endif  // 10.7
-
-// Replicate specific 10.9 SDK declarations for building with prior SDKs.
-#if !defined(MAC_OS_X_VERSION_10_9) || \
-    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_9
-
-@interface NSView (MavericksAPI)
-// Flatten all child views that did not call setWantsLayer:YES into this
-// view's CALayer.
-- (void)setCanDrawSubviewsIntoLayer:(BOOL)flag;
-@end
-
-#endif  // MAC_OS_X_VERSION_10_9
-
 @implementation NSView (ChromeAdditions)
 
 - (CGFloat)cr_lineWidth {