Cleanup handoff_manager.h header.

Moves ivars to implementation files and moves the objc_property_releaser
include into implementation file, so that code built with  ARC can
depend on it.

BUG=None

Review-Url: https://codereview.chromium.org/2536073003
Cr-Commit-Position: refs/heads/master@{#435004}

components/handoff/handoff_manager.h

@@ -7,7 +7,6 @@
 
 #include <Foundation/Foundation.h>
 
-#include "base/mac/objc_property_releaser.h"
 #include "build/build_config.h"
 #include "components/handoff/handoff_utility.h"
 #include "url/gurl.h"
@@ -22,14 +21,7 @@ class PrefRegistrySyncable;
 
 // Maintains all of the state relevant to the Handoff feature. Allows Chrome to
 // hand off the current active URL to other devices.
-@interface HandoffManager : NSObject {
- @private
-  base::mac::ObjCPropertyReleaser _propertyReleaser_HandoffManager;
-
-  GURL _activeURL;
-  NSUserActivity* _userActivity;
-  handoff::Origin _origin;
-}
+@interface HandoffManager : NSObject
 
 #if defined(OS_IOS)
 // Registers preferences related to Handoff.

components/handoff/handoff_manager.mm

@@ -5,6 +5,7 @@
 #include "components/handoff/handoff_manager.h"
 
 #include "base/logging.h"
+#include "base/mac/objc_property_releaser.h"
 #include "base/mac/scoped_nsobject.h"
 #include "net/base/mac/url_conversions.h"
 
@@ -32,7 +33,12 @@
 
 @end
 
-@implementation HandoffManager
+@implementation HandoffManager {
+  base::mac::ObjCPropertyReleaser _propertyReleaser_HandoffManager;
+  GURL _activeURL;
+  NSUserActivity* _userActivity;
+  handoff::Origin _origin;
+}
 
 @synthesize userActivity = _userActivity;