Add decode() functionality to image elements.

third_party/WebKit/Source/core/exported/WebViewBase.h

Index: third_party/WebKit/Source/core/exported/WebViewBase.h
diff --git a/third_party/WebKit/Source/core/exported/WebViewBase.h b/third_party/WebKit/Source/core/exported/WebViewBase.h
index be06f3900a179bcc0ddabfe2a52eedd77d45140a..a80e23f9c0fd8b198528a3d9d57e3645c46230eb 100644
--- a/third_party/WebKit/Source/core/exported/WebViewBase.h
+++ b/third_party/WebKit/Source/core/exported/WebViewBase.h
@@ -125,6 +125,10 @@ class WebViewBase : public WebView, public RefCounted<WebViewBase> {
 
   virtual WebSettingsImpl* SettingsImpl() = 0;
 
+  virtual void RequestDecode(
+      sk_sp<SkImage>,
+      std::unique_ptr<WTF::Function<void(bool)>> callback) = 0;
+
   using WebWidget::GetPagePopup;
   virtual PagePopup* OpenPagePopup(PagePopupClient*) = 0;
   virtual void ClosePagePopup(PagePopup*) = 0;