Add glue for supporting custom MIME types in DataTransfer.

content/browser/renderer_host/clipboard_message_filter.cc

Index: content/browser/renderer_host/clipboard_message_filter.cc
diff --git a/content/browser/renderer_host/clipboard_message_filter.cc b/content/browser/renderer_host/clipboard_message_filter.cc
index cd4b6dfbd145f2af4852f45668e97f82189abcc8..1825b344dfbbb4e7178507c7c1722cd481f0e8e2 100644
--- a/content/browser/renderer_host/clipboard_message_filter.cc
+++ b/content/browser/renderer_host/clipboard_message_filter.cc
@@ -62,6 +62,7 @@ bool ClipboardMessageFilter::OnMessageReceived(const IPC::Message& message,
     IPC_MESSAGE_HANDLER(ClipboardHostMsg_ReadAsciiText, OnReadAsciiText)
     IPC_MESSAGE_HANDLER(ClipboardHostMsg_ReadHTML, OnReadHTML)
     IPC_MESSAGE_HANDLER_DELAY_REPLY(ClipboardHostMsg_ReadImage, OnReadImage)
+    IPC_MESSAGE_HANDLER(ClipboardHostMsg_ReadCustomData, OnReadCustomData)
 #if defined(OS_MACOSX)
     IPC_MESSAGE_HANDLER(ClipboardHostMsg_FindPboardWriteStringAsync,
                         OnFindPboardWriteString)
@@ -195,6 +196,11 @@ void ClipboardMessageFilter::OnReadImageReply(
   Send(reply_msg);
 }
 
+void ClipboardMessageFilter::OnReadCustomData(
+    ui::Clipboard::Buffer buffer, const string16& type, string16* result) {
+  GetClipboard()->ReadCustomData(buffer, type, result);
+}
+
 // static
 ui::Clipboard* ClipboardMessageFilter::GetClipboard() {
   // We have a static instance of the clipboard service for use by all message