mac: Use more modern API for writing images to the pasteboard.

ui/base/clipboard/clipboard_mac.mm

 // Copyright (c) 2012 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 "ui/base/clipboard/clipboard_mac.h"
 
 #import <Cocoa/Cocoa.h>
 #include <stdint.h>
 
 #include <limits>
@@ skipping 412 matching lines @@
   std::string url_str(url_data, url_len);
   NSString* url = base::SysUTF8ToNSString(url_str);
 
   base::scoped_nsobject<NSPasteboardItem> item(
       ClipboardUtil::PasteboardItemFromUrl(url, title));
   NSPasteboard* pb = GetPasteboard();
   ui::ClipboardUtil::AddDataToPasteboard(pb, item);
 }
 
 void ClipboardMac::WriteBitmap(const SkBitmap& bitmap) {
+  NSPasteboard* pb = GetPasteboard();
+  [pb clearContents];
   NSImage* image = skia::SkBitmapToNSImageWithColorSpace(
       bitmap, base::mac::GetSystemColorSpace());
-  // An API to ask the NSImage to write itself to the clipboard comes in 10.6 :(
-  // For now, spit out the image as a TIFF.
-  NSPasteboard* pb = GetPasteboard();
-  [pb addTypes:[NSArray arrayWithObject:NSTIFFPboardType] owner:nil];
-  NSData* tiff_data = [image TIFFRepresentation];
-  LOG_IF(ERROR, tiff_data == NULL) << "Failed to allocate image for clipboard";
-  if (tiff_data) {
-    [pb setData:tiff_data forType:NSTIFFPboardType];
-  }
+  [pb writeObjects:@[ image ]];
 }
 
 void ClipboardMac::WriteData(const FormatType& format,
                              const char* data_data,
                              size_t data_len) {
   NSPasteboard* pb = GetPasteboard();
   [pb addTypes:[NSArray arrayWithObject:format.ToNSString()] owner:nil];
   [pb setData:[NSData dataWithBytes:data_data length:data_len]
       forType:format.ToNSString()];
 }
 
 // Write an extra flavor that signifies WebKit was the last to modify the
 // pasteboard. This flavor has no data.
 void ClipboardMac::WriteWebSmartPaste() {
   NSPasteboard* pb = GetPasteboard();
   NSString* format = GetWebKitSmartPasteFormatType().ToNSString();
   [pb addTypes:[NSArray arrayWithObject:format] owner:nil];
   [pb setData:nil forType:format];
 }
 
 }  // namespace ui