Auto merge of #195 - jrmuizel:backing, r=jdm

Add convertRectToBacking to NSView

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cocoa/src/appkit.rs

@@ -1673,6 +1673,7 @@ pub trait NSView: Sized {
 
     unsafe fn widthAnchor(self) -> id;
     unsafe fn heightAnchor(self) -> id;
+    unsafe fn convertRectToBacking(self, rect: NSRect) -> NSRect;
 }
 
 impl NSView for id {
@@ -1743,6 +1744,10 @@ impl NSView for id {
     unsafe fn heightAnchor(self) -> id {
         msg_send![self, heightAnchor]
     }
+
+    unsafe fn convertRectToBacking(self, rect: NSRect) -> NSRect {
+        msg_send![self, convertRectToBacking:rect]
+    }
 }
 
 pub type NSAutoresizingMaskOptions = u64;