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

ui/base/clipboard/clipboard_gtk.cc

Index: ui/base/clipboard/clipboard_gtk.cc
diff --git a/ui/base/clipboard/clipboard_gtk.cc b/ui/base/clipboard/clipboard_gtk.cc
index b3666be3c43318582f21f5c59a6e925f8b759c64..40c58ca47321c38969e648a44a30a864fbb84066 100644
--- a/ui/base/clipboard/clipboard_gtk.cc
+++ b/ui/base/clipboard/clipboard_gtk.cc
@@ -108,6 +108,7 @@ GdkFilterReturn SelectionChangeObserver::OnXEvent(GdkXEvent* xevent,
 
 const char kMimeTypeBitmap[] = "image/bmp";
 const char kMimeTypeMozillaURL[] = "text/x-moz-url";
+const char kMimeTypePepperCustomData[] = "chromium/x-pepper-custom-data";
 const char kMimeTypeWebkitSmartPaste[] = "chromium/x-webkit-paste";
 
 std::string GdkAtomToString(const GdkAtom& atom) {
@@ -650,6 +651,12 @@ const Clipboard::FormatType& Clipboard::GetWebCustomDataFormatType() {
   return type;
 }
 
+// static
+const Clipboard::FormatType& Clipboard::GetPepperCustomDataFormatType() {
+  CR_DEFINE_STATIC_LOCAL(FormatType, type, (kMimeTypePepperCustomData));
+  return type;
+}
+
 void Clipboard::InsertMapping(const char* key,
                               char* data,
                               size_t data_len) {