Move flash clipboard to the new proxy and add custom format support

ui/base/clipboard/clipboard_win.cc

Index: ui/base/clipboard/clipboard_win.cc
diff --git a/ui/base/clipboard/clipboard_win.cc b/ui/base/clipboard/clipboard_win.cc
index 6ea0cb17cec689c6bf6c53c85696cdbff44ea8ab..2a93859a42e7777879931f5ad38574ba590cb4b5 100644
--- a/ui/base/clipboard/clipboard_win.cc
+++ b/ui/base/clipboard/clipboard_win.cc
@@ -827,6 +827,15 @@ const Clipboard::FormatType& Clipboard::GetWebCustomDataFormatType() {
 }
 
 // static
+const Clipboard::FormatType& Clipboard::GetPepperCustomDataFormatType() {
+  CR_DEFINE_STATIC_LOCAL(
+      FormatType,
+      type,
+      (ClipboardUtil::GetPepperCustomDataFormat()->cfFormat));
+  return type;
+}
+
+// static
 void Clipboard::FreeData(unsigned int format, HANDLE data) {
   if (format == CF_BITMAP)
     ::DeleteObject(static_cast<HBITMAP>(data));