This CL clean up patch in DeviceMotionEvent.

Source/modules/device_orientation/DeviceMotionEvent.cpp

Index: Source/modules/device_orientation/DeviceMotionEvent.cpp
diff --git a/Source/modules/device_orientation/DeviceMotionEvent.cpp b/Source/modules/device_orientation/DeviceMotionEvent.cpp
index dda0e2da7c03a0cd06dfff3b6d1c7959c3749225..1fb8455ba3e7e305af5123173ad35d30c4ca1d52 100644
--- a/Source/modules/device_orientation/DeviceMotionEvent.cpp
+++ b/Source/modules/device_orientation/DeviceMotionEvent.cpp
@@ -63,7 +63,7 @@ void DeviceMotionEvent::initDeviceMotionEvent(const AtomicString& type, bool bub
 DeviceAcceleration* DeviceMotionEvent::acceleration()
 {
     if (!m_deviceMotionData->acceleration())
-        return 0;
+        return nullptr;
 
     if (!m_acceleration)
         m_acceleration = DeviceAcceleration::create(m_deviceMotionData->acceleration());
@@ -74,7 +74,7 @@ DeviceAcceleration* DeviceMotionEvent::acceleration()
 DeviceAcceleration* DeviceMotionEvent::accelerationIncludingGravity()
 {
     if (!m_deviceMotionData->accelerationIncludingGravity())
-        return 0;
+        return nullptr;
 
     if (!m_accelerationIncludingGravity)
         m_accelerationIncludingGravity = DeviceAcceleration::create(m_deviceMotionData->accelerationIncludingGravity());
@@ -85,7 +85,7 @@ DeviceAcceleration* DeviceMotionEvent::accelerationIncludingGravity()
 DeviceRotationRate* DeviceMotionEvent::rotationRate()
 {
     if (!m_deviceMotionData->rotationRate())
-        return 0;
+        return nullptr;
 
     if (!m_rotationRate)
         m_rotationRate = DeviceRotationRate::create(m_deviceMotionData->rotationRate());