Absolute Device Orientation API: blink implementation.

third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp

Index: third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp
diff --git a/third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp b/third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp
index 4899a6e35b7621d24b543680f2be578ca985b2f7..21bf0347941961f069e7ad92e0b260f92edd38b1 100644
--- a/third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp
+++ b/third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp
@@ -54,6 +54,7 @@
 #include "modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.h"
 #include "modules/device_light/DeviceLightController.h"
 #include "modules/device_orientation/DeviceMotionController.h"
+#include "modules/device_orientation/DeviceOrientationAbsoluteController.h"
 #include "modules/device_orientation/DeviceOrientationController.h"
 #include "modules/encryptedmedia/HTMLMediaElementEncryptedMedia.h"
 #include "modules/gamepad/NavigatorGamepad.h"
@@ -139,6 +140,8 @@ void FrameLoaderClientImpl::dispatchDidClearWindowObjectInMainWorld()
         if (document) {
             DeviceMotionController::from(*document);
             DeviceOrientationController::from(*document);
+            if (RuntimeEnabledFeatures::deviceOrientationAbsoluteEnabled())
+                DeviceOrientationAbsoluteController::from(*document);

[haraken, 2015/10/29 14:15:11]

If the runtime flag is enabled, won't it happen that the same object is
double-registered to the Document's supplement map?

It will cause a problem because when the Document dies, the Document calls
destructors for all supplement objects in the map. If the same object is
double-registered, the second destructor call will cause double-free.

That's why I'm concerned about implementing supplementName() on multiple classes
in the same hierarchy.

[timvolodine, 2015/10/29 19:34:33]

If understand correctly the point about supplementName() is that we are actually
hiding the super class methods. If somebody static_casts the 'absolute'
controller to its super class and then invokes supplementName() it would give
the name of the super class.

However I don't see this kind of usage in current code and don't think it's
possible to have the same object twice in the map.

If having a supplementName as part of class is a concern perhaps a solution
could be to put it into anonymous namespace in the .cpp... or extract a common
DeviceOrientationBase class and make the others derive from it while
implementing static methods. wdyt?

             if (RuntimeEnabledFeatures::deviceLightEnabled())
                 DeviceLightController::from(*document);
             NavigatorGamepad::from(*document);