Register clipboard image blob in the browser process to copy data less.

content/renderer/webclipboard_impl.h

Index: content/renderer/webclipboard_impl.h
diff --git a/content/renderer/webclipboard_impl.h b/content/renderer/webclipboard_impl.h
index 3bdc568bcddb380cdcc2adeb6db3fe6cfb6e863a..6a3d82b574117086f341603757c07714ce7f4ae1 100644
--- a/content/renderer/webclipboard_impl.h
+++ b/content/renderer/webclipboard_impl.h
@@ -33,7 +33,7 @@ class WebClipboardImpl : public blink::WebClipboard {
                             blink::WebURL* source_url,
                             unsigned* fragment_start,
                             unsigned* fragment_end) override;
-  blink::WebData readImage(Buffer buffer) override;
+  blink::WebBlobInfo readImage(Buffer buffer) override;
   blink::WebString readCustomData(Buffer buffer,
                                   const blink::WebString& type) override;
   void writePlainText(const blink::WebString& plain_text) override;