Trigger style recalc when the window's active state change

Source/core/frame/FrameView.cpp

Index: Source/core/frame/FrameView.cpp
diff --git a/Source/core/frame/FrameView.cpp b/Source/core/frame/FrameView.cpp
index 80bbf1b9c1caa164c41519188afb2ff8c9b8d76d..91e39d20d46521af7d21bb4113a88d6c4e793883 100644
--- a/Source/core/frame/FrameView.cpp
+++ b/Source/core/frame/FrameView.cpp
@@ -341,6 +341,20 @@ void FrameView::recalculateCustomScrollbarStyle()
     }
 }
 
+void FrameView::invalidateAllCustomScrollbarsOnActiveChanged()
+{
+    const ChildrenWidgetSet* viewChildren = children();
+    for (const RefPtrWillBeMember<Widget>& child : *viewChildren) {
+        Widget* widget = child.get();
+        if (widget->isFrameView()) {
+            toFrameView(widget)->recalculateCustomScrollbarStyle();
+            toFrameView(widget)->invalidateAllCustomScrollbarsOnActiveChanged();

[skobes, 2014/12/08 21:48:04]

Sorry to revisit this but I am still confused by the recursive descent.  Doesn't
the iframe have its own FrameSelection object?  Is there some reason we would
get FrameSelection::focusedOrActiveStateChanged() only for the topmost frame?

[MuVen, 2014/12/09 09:33:07]

Actually as i see there is an issue in the FrameSelection even. I have raised
issue for the same @ crbug.com/440313. Only focused element shouldnt be
invalidated. window-inactive css needs to be applied for all the elements with
in the document which has window-inactive css.

+        } else if (widget->isScrollbar()) {
+            toScrollbar(widget)->styleChanged();
+        }
+    }
+}
+
 void FrameView::recalculateScrollbarOverlayStyle()
 {
     ScrollbarOverlayStyle oldOverlayStyle = scrollbarOverlayStyle();