[Android] Adding Smart GO/NEXT feature in Chrome

third_party/WebKit/Source/core/page/FocusController.cpp

 /*
  * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nuanti Ltd.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 29 matching lines @@
 #include "core/editing/FrameSelection.h"
 #include "core/editing/InputMethodController.h"
 #include "core/events/Event.h"
 #include "core/frame/FrameClient.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/RemoteFrame.h"
 #include "core/frame/Settings.h"
 #include "core/html/HTMLAreaElement.h"
+#include "core/html/HTMLFormElement.h"
 #include "core/html/HTMLImageElement.h"
 #include "core/html/HTMLPlugInElement.h"
 #include "core/html/HTMLShadowElement.h"
 #include "core/html/HTMLSlotElement.h"
 #include "core/html/TextControlElement.h"
 #include "core/input/EventHandler.h"
 #include "core/layout/HitTestResult.h"
+#include "core/layout/LayoutObject.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/FocusChangedObserver.h"
 #include "core/page/FrameTree.h"
 #include "core/page/Page.h"
 #include "core/page/SpatialNavigation.h"
 
 #include <limits>
 
 namespace blink {
 
@@ skipping 992 matching lines @@
 }
 
 Element* FocusController::FindFocusableElement(WebFocusType type,
                                                Element& element) {
   // FIXME: No spacial navigation code yet.
   DCHECK(type == kWebFocusTypeForward || type == kWebFocusTypeBackward);
   ScopedFocusNavigation scope = ScopedFocusNavigation::CreateFor(element);
   return FindFocusableElementAcrossFocusScopes(type, scope);
 }
 
+Element* FocusController::NextFocusableElementInForm(Element* element,
+                                                     WebFocusType focus_type) {
+  if (!element->IsFormControlElement() &&
+      !ToHTMLElement(element)->isContentEditableForBinding())
+    return nullptr;
+
+  HTMLFormElement* form_owner = nullptr;
+  if (ToHTMLElement(element)->isContentEditableForBinding())
+    form_owner = Traversal<HTMLFormElement>::FirstAncestor(*element);
+  else
+    form_owner = ToHTMLFormControlElement(element)->formOwner();
+
+  if (!form_owner)
+    return nullptr;
+
+  Element* next_element = element;
+  for (next_element = FindFocusableElement(focus_type, *next_element);
+       next_element;
+       next_element = FindFocusableElement(focus_type, *next_element)) {
+    if (ToHTMLElement(next_element)->isContentEditableForBinding() &&
+        next_element->IsDescendantOf(form_owner))
+      return next_element;
+    if (!next_element->IsFormControlElement())
+      continue;
+    HTMLFormControlElement* form_element =
+        ToHTMLFormControlElement(next_element);
+    if (form_element->formOwner() != form_owner ||
+        form_element->IsDisabledOrReadOnly())
+      continue;
+    LayoutObject* layout = next_element->GetLayoutObject();
+    if (layout && layout->IsTextControl()) {
+      // TODO(ajith.v) Extend it for select elements, radio buttons and check
+      // boxes
+      return next_element;
+    }
+  }
+  return nullptr;
+}
+
 Element* FocusController::FindFocusableElementInShadowHost(
     const Element& shadow_host) {
   DCHECK(shadow_host.AuthorShadowRoot());
   ScopedFocusNavigation scope =
       ScopedFocusNavigation::OwnedByShadowHost(shadow_host);
   return FindFocusableElementAcrossFocusScopes(kWebFocusTypeForward, scope);
 }
 
 static bool RelinquishesEditingFocus(const Element& element) {
   DCHECK(HasEditableStyle(element));
@@ skipping 331 matching lines @@
     it->FocusedFrameChanged();
 }
 
 DEFINE_TRACE(FocusController) {
   visitor->Trace(page_);
   visitor->Trace(focused_frame_);
   visitor->Trace(focus_changed_observers_);
 }
 
 }  // namespace blink