[core] Add NIInterfaceOrientation.

src/core/src/NIDeviceOrientation.m

@@ -19,6 +19,21 @@
 #import "NimbusCore.h"
 
 
+///////////////////////////////////////////////////////////////////////////////////////////////////
+UIInterfaceOrientation NIInterfaceOrientation() {
+  UIInterfaceOrientation orient = [UIApplication sharedApplication].statusBarOrientation;
+
+  // This code used to use the navigator to find the currently visible view controller and
+  // fall back to checking its orientation if we didn't know the status bar's orientation.
+  // It's unclear when this was actually necessary, though, so this assertion is here to try
+  // to find that case. If this assertion fails then the repro case needs to be analyzed and
+  // this method made more robust to handle that case.
+  NIDASSERT(UIDeviceOrientationUnknown != orient);
+
+  return orient;
+}
+
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 BOOL NIIsSupportedOrientation(UIInterfaceOrientation orientation) {
   if (NIIsPad()) {

src/core/src/NimbusCore.h

@@ -402,6 +402,13 @@ CGRect NIRectInset(CGRect rect, UIEdgeInsets insets);
  */
 BOOL NIIsSupportedOrientation(UIInterfaceOrientation orientation);
 
+/**
+ * @brief Returns the application's current interface orientation.
+ *
+ * @returns The current interface orientation.
+ */
+UIInterfaceOrientation NIInterfaceOrientation();
+
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 /**@}*/// End of Device Orientation ///////////////////////////////////////////////////////////////