frame()->host() may be null in ScreenOrientationController::pageVisibilityChanged

third_party/WebKit/Source/modules/screen_orientation/ScreenOrientationController.cpp

Index: third_party/WebKit/Source/modules/screen_orientation/ScreenOrientationController.cpp
diff --git a/third_party/WebKit/Source/modules/screen_orientation/ScreenOrientationController.cpp b/third_party/WebKit/Source/modules/screen_orientation/ScreenOrientationController.cpp
index 4fbe3257e9f57bba77746d3630823ff0e6cfcc88..150135369a44af01d60d46081065e50b0187ce7b 100644
--- a/third_party/WebKit/Source/modules/screen_orientation/ScreenOrientationController.cpp
+++ b/third_party/WebKit/Source/modules/screen_orientation/ScreenOrientationController.cpp
@@ -93,7 +93,7 @@ void ScreenOrientationController::updateOrientation()
 
 bool ScreenOrientationController::isActiveAndVisible() const
 {
-    return m_orientation && frame() && page() && page()->isPageVisible();
+    return m_orientation && m_client && frame() && page() && page()->isPageVisible();
 }
 
 void ScreenOrientationController::pageVisibilityChanged()
@@ -103,6 +103,9 @@ void ScreenOrientationController::pageVisibilityChanged()
     if (!isActiveAndVisible())
         return;
 
+    DCHECK(frame());
+    DCHECK(frame()->host());
+
     // The orientation type and angle are tied in a way that if the angle has
     // changed, the type must have changed.
     unsigned short currentAngle = frame()->host()->chromeClient().screenInfo().orientationAngle;