[screen-orientation] Update implementation to match recent spec changes.

Source/modules/screen_orientation/ScreenOrientationController.cpp

Index: Source/modules/screen_orientation/ScreenOrientationController.cpp
diff --git a/Source/modules/screen_orientation/ScreenOrientationController.cpp b/Source/modules/screen_orientation/ScreenOrientationController.cpp
index af35b986950871a69d10afc1166fb7977f197568..e8b8c133e35e8f05fbdfde2407d21aee35e7be69 100644
--- a/Source/modules/screen_orientation/ScreenOrientationController.cpp
+++ b/Source/modules/screen_orientation/ScreenOrientationController.cpp
@@ -5,11 +5,11 @@
 #include "config.h"
 #include "modules/screen_orientation/ScreenOrientationController.h"
 
-#include "core/frame/LocalDOMWindow.h"
+#include "core/events/Event.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
-#include "core/frame/Screen.h"
 #include "core/page/Page.h"
+#include "modules/screen_orientation/ScreenOrientation.h"
 #include "platform/LayoutTestSupport.h"
 #include "platform/PlatformScreen.h"
 #include "public/platform/WebScreenOrientationClient.h"
@@ -28,18 +28,19 @@ void ScreenOrientationController::persistentHostHasBeenDestroyed()
 
 void ScreenOrientationController::provideTo(LocalFrame& frame, blink::WebScreenOrientationClient* client)
 {
+    ASSERT(RuntimeEnabledFeatures::screenOrientationEnabled());
+
     ScreenOrientationController* controller = new ScreenOrientationController(frame, client);
     WillBeHeapSupplement<LocalFrame>::provideTo(frame, supplementName(), adoptPtrWillBeNoop(controller));
 }
 
-ScreenOrientationController& ScreenOrientationController::from(LocalFrame& frame)
+ScreenOrientationController* ScreenOrientationController::from(LocalFrame& frame)
 {
-    return *static_cast<ScreenOrientationController*>(WillBeHeapSupplement<LocalFrame>::from(frame, supplementName()));
+    return static_cast<ScreenOrientationController*>(WillBeHeapSupplement<LocalFrame>::from(frame, supplementName()));
 }
 
 ScreenOrientationController::ScreenOrientationController(LocalFrame& frame, blink::WebScreenOrientationClient* client)
     : PageLifecycleObserver(frame.page())
-    , m_overrideOrientation(blink::WebScreenOrientationUndefined)
     , m_client(client)
     , m_frame(frame)
 {
@@ -77,33 +78,9 @@ blink::WebScreenOrientationType ScreenOrientationController::computeOrientation(
     }
 }
 
-void ScreenOrientationController::pageVisibilityChanged()
+void ScreenOrientationController::updateOrientation()
 {
-    if (page() && page()->visibilityState() == PageVisibilityStateVisible) {
-        blink::WebScreenOrientationType oldOrientation = m_overrideOrientation;
-        m_overrideOrientation = blink::WebScreenOrientationUndefined;
-        // 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() && oldOrientation != orientation())
-            m_frame.sendOrientationChangeEvent();
-    } else if (m_overrideOrientation == blink::WebScreenOrientationUndefined) {
-        // The page is no longer visible, store the last know screen orientation
-        // so that we keep returning this orientation until the page becomes
-        // visible again.
-        m_overrideOrientation = orientation();
-    }
-}
-
-blink::WebScreenOrientationType ScreenOrientationController::orientation() const
-{
-    if (m_overrideOrientation != blink::WebScreenOrientationUndefined) {
-        // The page is not visible, keep returning the last known screen orientation.
-        ASSERT(!page() || page()->visibilityState() != PageVisibilityStateVisible);
-        return m_overrideOrientation;
-    }
+    ASSERT(m_orientation);
 
     blink::WebScreenOrientationType orientationType = screenOrientationType(m_frame.view());
     if (orientationType == blink::WebScreenOrientationUndefined) {
@@ -111,10 +88,66 @@ blink::WebScreenOrientationType ScreenOrientationController::orientation() const
         orientationType = computeOrientation(m_frame.view());
     }
     ASSERT(orientationType != blink::WebScreenOrientationUndefined);
-    return orientationType;
+
+    m_orientation->setType(orientationType);
+    m_orientation->setAngle(screenOrientationAngle(m_frame.view()));
+}
+
+void ScreenOrientationController::pageVisibilityChanged()
+{
+    if (!m_orientation || !page() || page()->visibilityState() != PageVisibilityStateVisible)
+        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());
+
+    // 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)
+        notifyOrientationChanged();
+}
+
+void ScreenOrientationController::notifyOrientationChanged()
+{
+    ASSERT(RuntimeEnabledFeatures::screenOrientationEnabled());
+
+    if (!m_orientation || !page() || page()->visibilityState() != PageVisibilityStateVisible)
+        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.
+    Vector<RefPtr<LocalFrame> > childFrames;
+    for (Frame* child = m_frame.tree().firstChild(); child; child = child->tree().nextSibling()) {
+        if (child->isLocalFrame())
+            childFrames.append(toLocalFrame(child));
+    }
+
+    // Notify current orientation object.
+    m_orientation->dispatchEvent(Event::create(EventTypeNames::change));
+
+    // ... and child frames, if they have a ScreenOrientationController.
+    for (size_t i = 0; i < childFrames.size(); ++i) {
+        ScreenOrientationController* controller = ScreenOrientationController::from(*childFrames[i]);
+        if (controller)
+            controller->notifyOrientationChanged();
+    }
 }
 
-void ScreenOrientationController::lockOrientation(blink::WebScreenOrientationLockType orientation, blink::WebLockOrientationCallback* callback)
+void ScreenOrientationController::setOrientation(ScreenOrientation* orientation)
+{
+    m_orientation = orientation;
+    if (m_orientation)
+        updateOrientation();
+}
+
+void ScreenOrientationController::lock(blink::WebScreenOrientationLockType orientation, blink::WebLockOrientationCallback* callback)
 {
     if (!m_client) {
         return;
@@ -123,7 +156,7 @@ void ScreenOrientationController::lockOrientation(blink::WebScreenOrientationLoc
     m_client->lockOrientation(orientation, callback);
 }
 
-void ScreenOrientationController::unlockOrientation()
+void ScreenOrientationController::unlock()
 {
     if (!m_client) {
         return;
@@ -132,4 +165,15 @@ void ScreenOrientationController::unlockOrientation()
     m_client->unlockOrientation();
 }
 
+const LocalFrame& ScreenOrientationController::frame() const
+{
+    return m_frame;
+}
+
+void ScreenOrientationController::trace(Visitor* visitor)
+{
+    visitor->trace(m_orientation);
+    WillBeHeapSupplement<LocalFrame>::trace(visitor);
+}
+
 } // namespace WebCore