Add decode() functionality to image elements.

third_party/WebKit/Source/web/WebViewImpl.cpp

Index: third_party/WebKit/Source/web/WebViewImpl.cpp
diff --git a/third_party/WebKit/Source/web/WebViewImpl.cpp b/third_party/WebKit/Source/web/WebViewImpl.cpp
index 3dfa0a38658bc8eda5484c587ddc9a7187093135..2ce530415d5a1f99987446fb377ff932ce6010b0 100644
--- a/third_party/WebKit/Source/web/WebViewImpl.cpp
+++ b/third_party/WebKit/Source/web/WebViewImpl.cpp
@@ -3499,6 +3499,13 @@ WebInputMethodController* WebViewImpl::GetActiveWebInputMethodController()
   return local_frame ? local_frame->GetInputMethodController() : nullptr;
 }
 
+void WebViewImpl::RequestDecode(
+    sk_sp<SkImage> image,
+    std::unique_ptr<WTF::Function<void(bool)>> callback) {
+  layer_tree_view_->RequestDecode(std::move(image),
+                                  ConvertToBaseCallback(std::move(callback)));
+}
+
 Color WebViewImpl::BaseBackgroundColor() const {
   return base_background_color_override_enabled_
              ? base_background_color_override_