Adding support for Smart GO NEXT feature in Android Chrome

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index b1e7118cb1f524e3f2a50c6ef76f72406a734d44..94a73155ff805d826109ef4a55a52ce001e2db7b 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -116,6 +116,7 @@
 #include "public/platform/WebCompositeAndReadbackAsyncCallback.h"
 #include "public/platform/WebDragData.h"
 #include "public/platform/WebFloatPoint.h"
+#include "public/platform/WebFocusType.h"
 #include "public/platform/WebGestureCurve.h"
 #include "public/platform/WebImage.h"
 #include "public/platform/WebLayerTreeView.h"
@@ -2519,9 +2520,67 @@ int WebViewImpl::textInputFlags()
         }
     }
 
+    if (isListeningToKeyboardEvents(*element))
+        flags |= WebTextInputFlagListeningToKeyboardEvents;
+
+    if (nextFocusableElement(element, WebFocusTypeForward))
+        flags |= WebTextInputFlagHaveNextFocusableElement;
+
+    if (nextFocusableElement(element, WebFocusTypeBackward))
+        flags |= WebTextInputFlagHavePreviousFocusableElement;
+
     return flags;
 }
 
+Element* WebViewImpl::nextFocusableElement(Element* element, WebFocusType focusType)
+{
+    if (!element->isFormControlElement())
+        return nullptr;
+
+    HTMLFormControlElement* formControlElement = toHTMLFormControlElement(element);
+    HTMLFormElement* formOwner = formControlElement->formOwner();
+    if (!formOwner)
+        return nullptr;
+
+    Node* nextNode = element;
+    while ((nextNode = page()->focusController().findFocusableNode(focusType, *nextNode))) {
+        if (!toElement(nextNode)->isFormControlElement())
+            continue;
+        HTMLFormControlElement* formElement = toHTMLFormControlElement(nextNode);
+        if (formElement->formOwner() != formOwner)
+            continue;
+        LayoutObject* layout = nextNode->layoutObject();
+        if (nextNode->isContentEditable() || (layout && layout->isTextControl())) {
+            // TODO(AKV) Extend it for Select element, Radio button and Check boxes
+            return toElement(nextNode);
+        }
+    }
+    return nullptr;
+}
+
+bool WebViewImpl::isListeningToKeyboardEvents(const Element& element)
+{
+    if (!element.isFormControlElement())
+        return false;
+
+    return (element.hasEventListeners(EventTypeNames::keydown) || element.hasEventListeners(EventTypeNames::keypress) || element.hasEventListeners(EventTypeNames::keyup));
+}
+
+void WebViewImpl::advanceFocusToNextInputField(WebFocusType focusType)
+{
+    Element* element = focusedElement();
+    if (!element)
+        return;
+
+    Element* nextElement = nextFocusableElement(element, focusType);
+    if (!nextElement)
+        return;
+
+    RefPtrWillBeRawPtr<Element> nextFocusElement = nextElement;
+    nextFocusElement->scrollIntoViewIfNeeded(true /*centerIfNeeded*/);
+    nextFocusElement->focus(false, focusType);
+}
+
 WebString WebViewImpl::inputModeOfFocusedElement()
 {
     if (!RuntimeEnabledFeatures::inputModeAttributeEnabled())