[iOS] Upstream iOS geolocation code

ios/chrome/browser/geolocation/CLLocation+XGeoHeader.h

Index: ios/chrome/browser/geolocation/CLLocation+XGeoHeader.h
diff --git a/ios/chrome/browser/geolocation/CLLocation+XGeoHeader.h b/ios/chrome/browser/geolocation/CLLocation+XGeoHeader.h
new file mode 100644
index 0000000000000000000000000000000000000000..f2de7d64b0938fcfddb737e963ac6be27059d5ec
--- /dev/null
+++ b/ios/chrome/browser/geolocation/CLLocation+XGeoHeader.h
@@ -0,0 +1,18 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef IOS_CHROME_BROWSER_GEOLOCATION_CLLOCATION_XGEOHEADER_H_
+#define IOS_CHROME_BROWSER_GEOLOCATION_CLLOCATION_XGEOHEADER_H_
+
+#import <CoreLocation/CoreLocation.h>
+
+@interface CLLocation (XGeoHeader)
+
+// Returns a string that encodes the location for use with the "X-Geo" HTTP
+// header field. The string is a base-64-encoded ASCII proto.
+- (NSString*)cr_xGeoString;
+
+@end
+
+#endif  // IOS_CHROME_BROWSER_GEOLOCATION_CLLOCATION_XGEOHEADER_H_