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 16ac66b81d9ca2ab9b1ce356f0d49aae56f04ae5..99830b13c0fd76fa0175d9529a11d2d1abb03882 100644
--- a/third_party/WebKit/Source/web/WebViewImpl.cpp
+++ b/third_party/WebKit/Source/web/WebViewImpl.cpp
@@ -3568,6 +3568,13 @@ 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_