diff -r 000000000000 -r 4f2f89ce4247 WebKit/mac/WebView/WebFrameViewPrivate.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebKit/mac/WebView/WebFrameViewPrivate.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2005 Apple Computer, Inc.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer. 
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution. 
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#import <WebKit/WebFrameView.h>
+
+@interface WebFrameView (WebPrivate)
+
+// FIXME: This method was used by Safari 4.0.x and older versions, but has not been used by any other WebKit
+// clients to my knowledge, and will not be used by future versions of Safari. It can probably be removed 
+// once we no longer need to keep nightly WebKit builds working with Safari 4.0.x and earlier.
+/*!
+    @method _largestChildWithScrollBars
+    @abstract Of the child WebFrameViews that are displaying scroll bars, determines which has the largest area.
+    @result A child WebFrameView that is displaying scroll bars, or nil if none.
+ */
+- (WebFrameView *)_largestChildWithScrollBars;
+
+// FIXME: This method was used by Safari 4.0.x and older versions, but has not been used by any other WebKit
+// clients to my knowledge, and will not be used by future versions of Safari. It can probably be removed 
+// once we no longer need to keep nightly WebKit builds working with Safari 4.0.x and earlier.
+/*!
+    @method _hasScrollBars
+    @result YES if at least one scroll bar is currently displayed
+ */
+- (BOOL)_hasScrollBars;
+
+/*!
+    @method _largestScrollableChild
+    @abstract Of the child WebFrameViews that allow scrolling, determines which has the largest area.
+    @result A child WebFrameView that is scrollable, or nil if none.
+ */
+- (WebFrameView *)_largestScrollableChild;
+
+/*!
+    @method _isScrollable
+    @result YES if scrolling is currently possible, whether or not scroll bars are currently showing. This
+    differs from -allowsScrolling in that the latter method only checks whether scrolling has been
+    explicitly disallowed via a call to setAllowsScrolling:NO.
+ */
+- (BOOL)_isScrollable;
+
+/*!
+    @method _contentView
+    @result The content view (NSClipView) of the WebFrameView's scroll view.
+ */
+- (NSClipView *)_contentView;
+
+/*!
+    @method _customScrollViewClass
+    @result The custom scroll view class that is installed, nil if the default scroll view is being used.
+ */
+- (Class)_customScrollViewClass;
+
+/*!
+    @method _setCustomScrollViewClass:
+    @result Switches the WebFrameView's scroll view class, this class needs to be a subclass of WebDynamicScrollBarsView.
+    Passing nil will switch back to the default WebDynamicScrollBarsView class.
+ */
+- (void)_setCustomScrollViewClass:(Class)scrollViewClass;
+
+@end