Introduce use counters for Blink specific editing event usage

Source/core/events/EventTarget.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  *           (C) 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ skipping 14 matching lines @@
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  */
 
 #include "config.h"
 #include "core/events/EventTarget.h"
 
+#include "EventTypeNames.h"
+#include "HTMLNames.h"
 #include "RuntimeEnabledFeatures.h"
 #include "bindings/v8/ExceptionState.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/NoEventDispatchAssertion.h"
 #include "core/events/Event.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/frame/DOMWindow.h"
+#include "core/frame/UseCounter.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/Vector.h"
 
 using namespace WTF;
 
 namespace WebCore {
 
 EventTargetData::EventTargetData()
 {
 }
@@ skipping 21 matching lines @@
     return 0;
 }
 
 inline DOMWindow* EventTarget::executingWindow()
 {
     if (ExecutionContext* context = executionContext())
         return context->executingWindow();
     return 0;
 }
 
+static void countByObjectType(const EventTarget* eventTarget, UseCounter::Feature featureOnInput, UseCounter::Feature featureOnTextArea, UseCounter::Feature featureOnContentEditable, UseCounter::Feature featureOnNonNode)
+{
+    UseCounter::Feature feature = featureOnNonNode;
+    if (const Node* node = const_cast<EventTarget*>(eventTarget)->toNode()) {
+        if (node->hasTagName(HTMLNames::inputTag))
+            feature = featureOnInput;
+        else if (node->hasTagName(HTMLNames::textareaTag))
+            feature = featureOnTextArea;
+        else
+            feature = featureOnContentEditable;
+    }
+    if (ExecutionContext* context = eventTarget->executionContext())
+        UseCounter::count(context, feature);
+}
+
 bool EventTarget::addEventListener(const AtomicString& eventType, PassRefPtr<EventListener> listener, bool useCapture)
 {
     // FIXME: listener null check should throw TypeError (and be done in
     // generated bindings), but breaks legacy content. http://crbug.com/249598
     if (!listener)
         return false;
+
+    if (eventType == EventTypeNames::textInput) {

[tkent, 2014/06/10 08:19:59]

EventTarget is a generic interface, and I feel adding feature-specific code like
this is not suitable.
Can you move the code to Editor, and call it from here?
Something like...

  if (DOMWInodow* window = executingWindow())
      window->frame()->editor().countEvents(eventType)


Also, you should count EventTarget::fireEventListeners rather than
addEventListeners because we can attach a listener to an ancestor node of the
target node.

[yosin_UTC9, 2014/06/11 00:48:20]

Done.

+        countByObjectType(this, UseCounter::TextInputEventOnInput,
+            UseCounter::TextInputEventOnTextArea,
+            UseCounter::TextInputEventOnContentEditable,
+            UseCounter::TextInputEventOnNotNode);
+    } else if (eventType == EventTypeNames::webkitBeforeTextInserted) {
+        countByObjectType(this, UseCounter::WebkitBeforeTextInsertedOnInput,
+            UseCounter::WebkitBeforeTextInsertedOnTextArea,
+            UseCounter::WebkitBeforeTextInsertedOnContentEditable,
+            UseCounter::WebkitBeforeTextInsertedOnNotNode);
+    } else if (eventType == EventTypeNames::webkitEditableContentChanged) {
+        countByObjectType(this, UseCounter::WebkitEditableContentChangedOnInput,
+            UseCounter::WebkitEditableContentChangedOnTextArea,
+            UseCounter::WebkitEditableContentChangedOnContentEditable,
+            UseCounter::WebkitEditableContentChangedOnNotNode);
+    }
+
     return ensureEventTargetData().eventListenerMap.add(eventType, listener, useCapture);
 }
 
 bool EventTarget::removeEventListener(const AtomicString& eventType, EventListener* listener, bool useCapture)
 {
     EventTargetData* d = eventTargetData();
     if (!d)
         return false;
 
     size_t indexOfRemovedListener;
@@ skipping 271 matching lines @@
     // they have one less listener to invoke.
     if (d->firingEventIterators) {
         for (size_t i = 0; i < d->firingEventIterators->size(); ++i) {
             d->firingEventIterators->at(i).iterator = 0;
             d->firingEventIterators->at(i).end = 0;
         }
     }
 }
 
 } // namespace WebCore