Refresh Frame(Loader) detach() related comments.

Source/core/frame/FrameView.h

Index: Source/core/frame/FrameView.h
diff --git a/Source/core/frame/FrameView.h b/Source/core/frame/FrameView.h
index b43bca84f56d5be7e33867fe71b007374cd43177..c246a8364e310d01931403727d4bdfa92454fe58 100644
--- a/Source/core/frame/FrameView.h
+++ b/Source/core/frame/FrameView.h
@@ -724,13 +724,12 @@ private:
     HashSet<RefPtr<LayoutPart>> m_parts;
 
     // The RefPtr cycle between LocalFrame and FrameView is broken
-    // when a LocalFrame is detached by FrameLoader::detachFromParent().
+    // when a LocalFrame is detached (LocalFrame::detach()).

[dcheng, 2015/07/13 17:27:51]

Personally, I think 'by' is a bit clearer since it avoids the double parens. But
I don't really care.

     // It clears the LocalFrame's m_view reference via setView(nullptr).
     //
     // For Oilpan, Member reference cycles pose no problem, but
-    // LocalFrame's FrameView is also cleared by setView(). This additionally
-    // triggers FrameView::dispose(), which performs the operations
-    // that cannot be delayed until finalization time.
+    // LocalFrame's FrameView is also cleared by setView() to keep
+    // the observable lifespan of LocalFrame::view() identical.
     RefPtrWillBeMember<LocalFrame> m_frame;
 
     WebDisplayMode m_displayMode;