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 854caa6ad9cf524eda5a754d235b4ff1352ce470..4a3a06c1c960bdb3ebf4bbd6dbee52231ee164b0 100644
--- a/third_party/WebKit/Source/web/WebViewImpl.cpp
+++ b/third_party/WebKit/Source/web/WebViewImpl.cpp
@@ -3534,6 +3534,13 @@ WebInputMethodControllerImpl* WebViewImpl::GetActiveWebInputMethodController()
   return WebInputMethodControllerImpl::FromFrame(FocusedLocalFrameInWidget());
 }
 
+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_