Reland 1: "mac: Allow Chrome to hand off its active URL to other devices."

components/handoff/handoff_manager.mm

Index: components/handoff/handoff_manager.mm
diff --git a/components/handoff/handoff_manager.mm b/components/handoff/handoff_manager.mm
new file mode 100644
index 0000000000000000000000000000000000000000..ab1efd693a5f701accbef39d1f56266cfb14f8eb
--- /dev/null
+++ b/components/handoff/handoff_manager.mm
@@ -0,0 +1,91 @@
+// Copyright 2014 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.
+
+#include "components/handoff/handoff_manager.h"
+
+#include "base/logging.h"
+#include "base/mac/scoped_nsobject.h"
+#include "components/handoff/handoff_utility.h"
+#include "net/base/mac/url_conversions.h"
+
+#if defined(OS_IOS)
+#include "base/ios/ios_util.h"
+#endif
+
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+#include "base/mac/mac_util.h"
+#include "base/mac/sdk_forward_declarations.h"
+#endif
+
+@interface HandoffManager ()
+
+// The active user activity.
+@property(nonatomic, retain) NSUserActivity* userActivity;
+
+// Whether the URL of the current tab should be exposed for Handoff.
+- (BOOL)shouldUseActiveURL;
+
+// Updates the active NSUserActivity.
+- (void)updateUserActivity;
+
+@end
+
+@implementation HandoffManager
+
+@synthesize userActivity = _userActivity;
+
+- (instancetype)init {
+  self = [super init];
+  if (self) {
+    _propertyReleaser_HandoffManager.Init(self, [HandoffManager class]);
+  }
+  return self;
+}
+
+- (void)updateActiveURL:(const GURL&)url {
+#if defined(OS_IOS)
+  // Handoff is only available on iOS 8+.
+  DCHECK(base::ios::IsRunningOnIOS8OrLater());
+#endif
+
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+  // Handoff is only available on OSX 10.10+.
+  DCHECK(base::mac::IsOSYosemiteOrLater());
+#endif
+
+  _activeURL = url;
+  [self updateUserActivity];
+}
+
+- (BOOL)shouldUseActiveURL {
+  return _activeURL.SchemeIsHTTPOrHTTPS();
+}
+
+- (void)updateUserActivity {
+  // Clear the user activity.
+  if (![self shouldUseActiveURL]) {
+    [self.userActivity invalidate];
+    self.userActivity = nil;
+    return;
+  }
+
+  // No change to the user activity.
+  const GURL userActivityURL(net::GURLWithNSURL(self.userActivity.webpageURL));
+  if (userActivityURL == _activeURL)
+    return;
+
+  // Invalidate the old user activity and make a new one.
+  [self.userActivity invalidate];
+
+  Class aClass = NSClassFromString(@"NSUserActivity");
+  NSUserActivity* userActivity = [[aClass performSelector:@selector(alloc)]
+      performSelector:@selector(initWithActivityType:)
+           withObject:handoff::kChromeHandoffActivityType];
+  self.userActivity = base::scoped_nsobject<NSUserActivity>(userActivity);
+  self.userActivity.webpageURL = net::NSURLWithGURL(_activeURL);
+  self.userActivity.userInfo = @{ handoff::kOriginKey : handoff::kOriginiOS };
+  [self.userActivity becomeCurrent];
+}
+
+@end