Implement the WebSmartPaste pasteboard type on Mac, stub it out on Linux, rem...

base/clipboard_mac.mm

 // Copyright (c) 2006-2008 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 "base/clipboard.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/logging.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
 
 namespace {
 
 // Would be nice if this were in UTCoreTypes.h, but it isn't
 const NSString* kUTTypeURLName = @"public.url-name";
 
+// Tells us if WebKit was the last to write to the pasteboard. There's no
+// actual data associated with this type.
+const NSString *kWebSmartPastePboardType = @"NeXT smart paste pasteboard type";
+
 NSPasteboard* GetPasteboard() {
   // The pasteboard should not be nil in a UI session, but this handy DCHECK
   // can help track down problems if someone tries using clipboard code outside
   // of a UI session.
   NSPasteboard* pasteboard = [NSPasteboard generalPasteboard];
   DCHECK(pasteboard);
   return pasteboard;
 }
 
 }  // namespace
@@ skipping 86 matching lines @@
       current_filename_offset = i + 1;
       continue;
     }
   }
 
   NSPasteboard* pb = GetPasteboard();
   [pb addTypes:[NSArray arrayWithObject:NSFilenamesPboardType] owner:nil];
   [pb setPropertyList:fileList forType:NSFilenamesPboardType];
 }
 
+// Write an extra flavor that signifies WebKit was the last to modify the
+// pasteboard. This flavor has no data.
+void Clipboard::WriteWebSmartPaste() {
+  NSPasteboard* pb = GetPasteboard();
+  [pb addTypes:[NSArray arrayWithObject:NSStringPboardType] owner:nil];
+  [pb setData:nil forType:GetWebKitSmartPasteFormatType()];
+}
+
 bool Clipboard::IsFormatAvailable(NSString* format) const {
   NSPasteboard* pb = GetPasteboard();
   NSArray* types = [pb types];
 
   return [types containsObject:format];
 }
 
 void Clipboard::ReadText(std::wstring* result) const {
   NSPasteboard* pb = GetPasteboard();
   NSString* contents = [pb stringForType:NSStringPboardType];
@@ skipping 109 matching lines @@
 
 // static
 Clipboard::FormatType Clipboard::GetFilenameWFormatType() {
   return NSFilenamesPboardType;
 }
 
 // static
 Clipboard::FormatType Clipboard::GetHtmlFormatType() {
   return NSHTMLPboardType;
 }
+
+// static
+Clipboard::FormatType Clipboard::GetWebKitSmartPasteFormatType() {
+  return kWebSmartPastePboardType;
+}