[Android] Adding Smart GO/NEXT feature in Chrome

third_party/WebKit/Source/core/editing/InputMethodController.cpp

Index: third_party/WebKit/Source/core/editing/InputMethodController.cpp
diff --git a/third_party/WebKit/Source/core/editing/InputMethodController.cpp b/third_party/WebKit/Source/core/editing/InputMethodController.cpp
index c64c0dc3716cc6c401fb5c2ca4eb8f8214422b33..a4783a0ad07de2a673b857963e54467c1ddf3998 100644
--- a/third_party/WebKit/Source/core/editing/InputMethodController.cpp
+++ b/third_party/WebKit/Source/core/editing/InputMethodController.cpp
@@ -30,6 +30,7 @@
 #include "core/InputTypeNames.h"
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
+#include "core/dom/ElementTraversal.h"
 #include "core/dom/Text.h"
 #include "core/editing/EditingUtilities.h"
 #include "core/editing/Editor.h"
@@ -39,12 +40,15 @@
 #include "core/editing/state_machines/ForwardCodePointStateMachine.h"
 #include "core/events/CompositionEvent.h"
 #include "core/frame/LocalFrame.h"
+#include "core/html/HTMLFormElement.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/html/HTMLTextAreaElement.h"
 #include "core/input/EventHandler.h"
 #include "core/layout/LayoutObject.h"
 #include "core/layout/LayoutTheme.h"
 #include "core/page/ChromeClient.h"
+#include "core/page/FocusController.h"
+#include "core/page/Page.h"
 
 namespace blink {
 
@@ -1109,9 +1113,75 @@ int InputMethodController::textInputFlags() const {
     }
   }
 
+  if (isListeningToKeyboardEvents(element))
+    flags |= WebTextInputFlagListeningToKeyboardEvents;
+
+  if (nextFocusableElementInForm(element, WebFocusTypeForward))
+    flags |= WebTextInputFlagHaveNextFocusableElement;
+
+  if (nextFocusableElementInForm(element, WebFocusTypeBackward))
+    flags |= WebTextInputFlagHavePreviousFocusableElement;
+
   return flags;
 }
 
+bool InputMethodController::isListeningToKeyboardEvents(
+    Element* element) const {
+  if (!element->isFormControlElement() &&
+      !toHTMLElement(element)->isContentEditableForBinding())
+    return false;
+  for (Node* node = element; node; node = node->parentNode()) {
+    if (node->hasEventListeners(EventTypeNames::keydown) ||
+        node->hasEventListeners(EventTypeNames::keypress) ||
+        node->hasEventListeners(EventTypeNames::keyup))
+      return true;
+  }
+  return false;
+}
+
+Element* InputMethodController::nextFocusableElementInForm(
+    Element* element,
+    WebFocusType focusType) const {
+  if (!element->isFormControlElement() &&
+      !toHTMLElement(element)->isContentEditableForBinding())
+    return nullptr;
+
+  HTMLFormElement* formOwner = nullptr;
+  if (toHTMLElement(element)->isContentEditableForBinding())
+    formOwner = Traversal<HTMLFormElement>::firstAncestor(*element);
+  else
+    formOwner = toHTMLFormControlElement(element)->formOwner();
+
+  if (!formOwner)
+    return nullptr;
+
+  Element* nextElement = element;
+  for (nextElement = document().page()->focusController().findFocusableElement(
+           focusType, *nextElement);
+       nextElement;
+       nextElement = document().page()->focusController().findFocusableElement(
+           focusType, *nextElement)) {
+    if (toHTMLElement(nextElement)->isContentEditableForBinding() &&
+        nextElement->isDescendantOf(formOwner))
+      return nextElement;
+    if (!nextElement->isFormControlElement())
+      continue;
+    HTMLFormControlElement* formElement = toHTMLFormControlElement(nextElement);
+    if (formElement->formOwner() != formOwner)
+      continue;
+    // Skip disabled or readonly editable elements.
+    if (formElement->isDisabledOrReadOnly())
+      continue;
+    LayoutObject* layout = nextElement->layoutObject();
+    if (layout && layout->isTextControl()) {
+      // TODO(ajith.v) Extend it for Select element, Radio button and Check
+      // boxes
+      return nextElement;
+    }
+  }
+  return nullptr;
+}
+
 WebTextInputMode InputMethodController::inputModeOfFocusedElement() const {
   if (!RuntimeEnabledFeatures::inputModeAttributeEnabled())
     return kWebTextInputModeDefault;