The link should be activated by enter key on focusing the child element inside the anchor(relanding)

Source/core/html/HTMLAnchorElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Simon Hausmann <hausmann@kde.org>
  * Copyright (C) 2003, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 129 matching lines @@
     int x = absolutePosition.x();
     int y = absolutePosition.y();
     url.append('?');
     url.appendNumber(x);
     url.append(',');
     url.appendNumber(y);
 }
 
 void HTMLAnchorElement::defaultEventHandler(Event* event)
 {
-    if (isLink()) {
-        if (focused() && isEnterKeyKeydownEvent(event) && isLiveLink()) {
+    if (isLiveLink()) {
+        if (isLinkEnterKey(event)) {
             event->setDefaultHandled();
             dispatchSimulatedClick(event);
             return;
         }
 
-        if (isLinkClick(event) && isLiveLink()) {
+        if (isLinkClick(event)) {
             handleClick(event);
             return;
         }
     }
 
     HTMLElement::defaultEventHandler(event);
 }
 
 void HTMLAnchorElement::setActive(bool down)
 {
@@ skipping 188 matching lines @@
     } else {
         request.setRequestContext(blink::WebURLRequest::RequestContextHyperlink);
         FrameLoadRequest frameRequest(&document(), request, getAttribute(targetAttr));
         frameRequest.setTriggeringEvent(event);
         if (hasRel(RelationNoReferrer))
             frameRequest.setShouldSendReferrer(NeverSendReferrer);
         frame->loader().load(frameRequest);
     }
 }
 
+bool HTMLAnchorElement::isLinkEnterKey(Event* event)
+{
+    if (isEnterKeyKeydownEvent(event)) {
+        if (focused())
+            return true;
+
+        ASSERT(event->target());
+        Node* target = event->target()->toNode();
+        ASSERT(target);
+
+        // if the target element is one of form controls or has contentEditable attribute on,
+        // we shouldn't simulate click action
+        if (target->focused() && !((target->isElementNode() && toElement(target)->isFormControlElement()) || target->isContentEditable()))

[robwu, 2014/10/03 13:28:40]

This logic is insufficient, because some form control elements can contain child
elements, and isFormControlElement() does not take the parent nodes into account
(isContentEditable() does look at the parent nodes though).

Here is an example:
<a> href="javascript:alert(0)">
  <button>
    Hello
    <b tabindex="1">
      world
    </b>
  </button>
</a>

Besides that, the Enter key should not be intercepted by every form control
element. For instance, in Firefox, the following code triggers an alert when
Enter is pressed:

<a href="javascript:alert('This is shown in Firefox')">
  <input type=text>
</a>

Track down all relevant defaultEventHandler calls (including non-form elements,
just in case), and check whether its defaultEventHandler implementation is
correct in terms of setting the eventHandled flag.
E.g. HTMLTextAreaElement::defaultEventHandler(Event* event) captures input
events using

    else if (renderer() && event->isBeforeTextInsertedEvent())
        handleBeforeTextInsertedEvent( ... event ... );

but does not call event->setDefaultHandled(true);
Consequently, the event is currently passed up in the DOM tree and ultimately
reaches the <a href> element, which causes a navigation to occur. This could be
fixed using

    else if (renderer() && event->isBeforeTextInsertedEvent()) {
        handleBeforeTextInsertedEvent( ... event ... );
        event->setDefaultHandled(true);
    }

+            return true;
+    }
+    return false;
+}
+
 bool isEnterKeyKeydownEvent(Event* event)
 {
     return event->type() == EventTypeNames::keydown && event->isKeyboardEvent() && toKeyboardEvent(event)->keyIdentifier() == "Enter";
 }
 
 bool isLinkClick(Event* event)
 {
     return event->type() == EventTypeNames::click && (!event->isMouseEvent() || toMouseEvent(event)->button() != RightButton);
 }
 
@@ skipping 15 matching lines @@
             Vector<String> argv;
             argv.append("a");
             argv.append(fastGetAttribute(hrefAttr));
             activityLogger->logEvent("blinkAddElement", argv.size(), argv.data());
         }
     }
     return HTMLElement::insertedInto(insertionPoint);
 }
 
 }