Make ScreenOrientationController a FrameDestructionObserver.

Source/modules/screen_orientation/ScreenOrientationController.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/screen_orientation/ScreenOrientationController.h"
 
 #include "core/events/Event.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
@@ skipping 17 matching lines @@
     ScreenOrientationController* controller = new ScreenOrientationController(frame, client);
     WillBeHeapSupplement<LocalFrame>::provideTo(frame, supplementName(), adoptPtrWillBeNoop(controller));
 }
 
 ScreenOrientationController* ScreenOrientationController::from(LocalFrame& frame)
 {
     return static_cast<ScreenOrientationController*>(WillBeHeapSupplement<LocalFrame>::from(frame, supplementName()));
 }
 
 ScreenOrientationController::ScreenOrientationController(LocalFrame& frame, WebScreenOrientationClient* client)
-    : PlatformEventController(frame.page())
+    : FrameDestructionObserver(&frame)
+    , PlatformEventController(frame.page())
     , m_client(client)
-    , m_frame(frame)
     , m_dispatchEventTimer(this, &ScreenOrientationController::dispatchEventTimerFired)
 {
 }
 
 const char* ScreenOrientationController::supplementName()
 {
     return "ScreenOrientationController";
 }
 
 // Compute the screen orientation using the orientation angle and the screen width / height.
@@ skipping 19 matching lines @@
         return isTallDisplay ? WebScreenOrientationLandscapeSecondary : WebScreenOrientationPortraitPrimary;
     default:
         ASSERT_NOT_REACHED();
         return WebScreenOrientationPortraitPrimary;
     }
 }
 
 void ScreenOrientationController::updateOrientation()
 {
     ASSERT(m_orientation);
+    ASSERT(frame());
 
-    WebScreenOrientationType orientationType = screenOrientationType(m_frame.view());
+    FrameView* view = frame()->view();
+    WebScreenOrientationType orientationType = screenOrientationType(view);
     if (orientationType == WebScreenOrientationUndefined) {
         // The embedder could not provide us with an orientation, deduce it ourselves.
-        orientationType = computeOrientation(m_frame.view());
+        orientationType = computeOrientation(view);
     }
     ASSERT(orientationType != WebScreenOrientationUndefined);
 
     m_orientation->setType(orientationType);
-    m_orientation->setAngle(screenOrientationAngle(m_frame.view()));
+    m_orientation->setAngle(screenOrientationAngle(view));
+}
+
+bool ScreenOrientationController::isActive() const

[mlamouri (slow - plz ping), 2014/09/23 10:29:49]

Could you rename this "isActiveAndVisible()"?

[sof, 2014/09/23 12:48:40]

Done.

+{
+    return m_orientation && frame() && page() && page()->visibilityState() == PageVisibilityStateVisible;
 }
 
 void ScreenOrientationController::pageVisibilityChanged()
 {
     notifyDispatcher();
 
-    if (!m_orientation || !page() || page()->visibilityState() != PageVisibilityStateVisible)
+    if (!isActive())
         return;
 
     // The orientation type and angle are tied in a way that if the angle has
     // changed, the type must have changed.
-    unsigned short currentAngle = screenOrientationAngle(m_frame.view());
+    unsigned short currentAngle = screenOrientationAngle(frame()->view());
 
     // FIXME: sendOrientationChangeEvent() currently send an event all the
     // children of the frame, so it should only be called on the frame on
     // top of the tree. We would need the embedder to call
     // sendOrientationChangeEvent on every WebFrame part of a WebView to be
     // able to remove this.
-    if (m_frame == m_frame.localFrameRoot() && m_orientation->angle() != currentAngle)
+    if (frame() == frame()->localFrameRoot() && m_orientation->angle() != currentAngle)
         notifyOrientationChanged();
 }
 
 void ScreenOrientationController::notifyOrientationChanged()
 {
     ASSERT(RuntimeEnabledFeatures::screenOrientationEnabled());
 
-    if (!m_orientation || !page() || page()->visibilityState() != PageVisibilityStateVisible)
+    if (!isActive())
         return;
 
     updateOrientation();
 
     // Keep track of the frames that need to be notified before notifying the
     // current frame as it will prevent side effects from the change event
     // handlers.
     WillBeHeapVector<RefPtrWillBeMember<LocalFrame> > childFrames;
-    for (Frame* child = m_frame.tree().firstChild(); child; child = child->tree().nextSibling()) {
+    for (Frame* child = frame()->tree().firstChild(); child; child = child->tree().nextSibling()) {
         if (child->isLocalFrame())
             childFrames.append(toLocalFrame(child));
     }
 
     // Notify current orientation object.
     if (!m_dispatchEventTimer.isActive())
         m_dispatchEventTimer.startOneShot(0, FROM_HERE);
 
     // ... and child frames, if they have a ScreenOrientationController.
     for (size_t i = 0; i < childFrames.size(); ++i) {
@@ skipping 15 matching lines @@
     ASSERT(m_client);
     m_client->lockOrientation(orientation, callback);
 }
 
 void ScreenOrientationController::unlock()
 {
     ASSERT(m_client);
     m_client->unlockOrientation();
 }
 
-const LocalFrame& ScreenOrientationController::frame() const
-{
-    return m_frame;
-}
-
 void ScreenOrientationController::dispatchEventTimerFired(Timer<ScreenOrientationController>*)
 {
     if (!m_orientation)
         return;
     m_orientation->dispatchEvent(Event::create(EventTypeNames::change));
 }
 
 void ScreenOrientationController::didUpdateData()
 {
     // Do nothing.
@@ skipping 18 matching lines @@
 {
     if (m_orientation && page()->visibilityState() == PageVisibilityStateVisible)
         startUpdating();
     else
         stopUpdating();
 }
 
 void ScreenOrientationController::trace(Visitor* visitor)
 {
     visitor->trace(m_orientation);
+    FrameDestructionObserver::trace(visitor);
     WillBeHeapSupplement<LocalFrame>::trace(visitor);
 }
 
 } // namespace blink