Merge 88396 - 2011-06-08 Sailesh Agrawal <sail@chromium.org>

Source/WebCore/platform/chromium/ScrollbarOverlayUtilitiesChromiumMac.mm

 /*
  * Copyright (C) 2008, 2011 Apple Inc. All Rights Reserved.
  * Copyright (C) 2011 Google 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
@@ skipping 42 matching lines @@
 @interface NSScrollerImp : NSObject
 
 + (id)scrollerImpWithStyle:(NSScrollerStyle)style
                controlSize:(NSControlSize)size
                 horizontal:(BOOL)horizontal
       replacingScrollerImp:(id)scroller;
 
 @property CGFloat knobAlpha;
 @property CGFloat trackAlpha;
 @property CGFloat knobProportion;
+@property NSInteger knobStyle;
 @property(getter=isEnabled) BOOL enabled;
 @property(getter=isHorizontal) BOOL horizontal;
 @property double doubleValue;
 @property(assign) id delegate;
 
 - (CGFloat)knobMinLength;
 - (CGFloat)trackBoxWidth;
 - (CGFloat)trackWidth;
 - (void)setBoundsSize:(NSSize)size;
 - (void)drawKnobSlotInRect:(NSRect)rect
                  highlight:(BOOL)flag;
 - (void)drawKnob;
 - (void)setOverlayScrollerState:(NSScrollerStyle)state
                forceImmediately:(BOOL)flag;
 - (void)setDelegate:(id)delegate;
+- (NSRect)rectForPart:(NSUInteger)arg1;
 
 @end
 
 // These are private APIs to manage overlay scrollbars.
 @interface NSScrollerImpPair : NSObject
 
 @property NSScrollerStyle scrollerStyle;
 @property(retain) NSScrollerImp *horizontalScrollerImp;
 @property(retain) NSScrollerImp *verticalScrollerImp;
 @property(assign) id delegate;
@@ skipping 27 matching lines @@
     return result;
 }
 
 static NSControlSize scrollbarControlSizeToNSControlSize(int controlSize)
 {
     return controlSize == WebCore::RegularScrollbar ? NSRegularControlSize : NSSmallControlSize;
 }
 
 static NSScrollerStyle preferredScrollerStyle()
 {
+    // TODO(sail): Disable overlay scrollbars for now until the following issues are fixed:
+    // #1: Invalidation issues causes the scrollbar to leave trailing artifacts.
+    // #2: Find tick marks need to be drawn on the scrollbar track.
+    return NSScrollerStyleLegacy;
+
     if ([NSScroller respondsToSelector:@selector(preferredScrollerStyle)])
         return [NSScroller preferredScrollerStyle];
     return NSScrollerStyleLegacy;
 }
 
 bool wkScrollbarPainterUsesOverlayScrollers(void)
 {
     return preferredScrollerStyle() == NSScrollerStyleOverlay;
 }
 
@@ skipping 17 matching lines @@
 {
     [painter setEnabled:enabled];
     [painter setBoundsSize:frameRect.size];
     [painter setDoubleValue:value];
     [painter setKnobProportion:proportion];
 
     if ([painter isHorizontal])
         frameRect.size.height = [painter trackWidth];
     else
         frameRect.size.width = [painter trackWidth];
+    frameRect.origin = NSZeroPoint;
 
     [painter drawKnobSlotInRect:frameRect highlight:NO];
     [painter drawKnob];
 }
 
 int wkScrollbarMinimumThumbLength(WKScrollbarPainterRef painter)
 {
     return [painter knobMinLength];
 }
 
@@ skipping 51 matching lines @@
         [controller setVerticalScrollerImp:painter];
 }
 
 void wkSetScrollbarPainterControllerStyle(WKScrollbarPainterControllerRef painter, int newStyle)
 {
     [painter setScrollerStyle:newStyle];
 }
 
 CGRect wkScrollbarPainterKnobRect(WKScrollbarPainterRef painter)
 {
-    return NSRectToCGRect(NSZeroRect);
+    return NSRectToCGRect([painter rectForPart:NSScrollerKnob]);
 }
 
 void wkSetScrollbarPainterKnobAlpha(WKScrollbarPainterRef painter, CGFloat alpha)
 {
     [painter setKnobAlpha:alpha];
 }
 
 void wkSetScrollbarPainterTrackAlpha(WKScrollbarPainterRef painter, CGFloat alpha)
 {
     [painter setTrackAlpha:alpha];
 }
 
 void wkSetScrollbarPainterKnobStyle(WKScrollbarPainterRef painter, wkScrollerKnobStyle style)
 {
-    // TODO(sail): A knob style API doesn't exist in the seeds currently available. 
+    [painter setKnobStyle:style];
 }
 
 WKScrollbarPainterControllerRef wkMakeScrollbarPainterController(id painterControllerDelegate)
 {
     if (!isScrollbarOverlayAPIAvailable())
         return nil;
     NSScrollerImpPair* controller = [[[lookUpNSScrollerImpPairClass() alloc] init] autorelease];
     [controller setDelegate:painterControllerDelegate];
     [controller setScrollerStyle:preferredScrollerStyle()];
     return controller;
@@ skipping 59 matching lines @@
     [controller endScrollGesture];
 }
 
 void wkScrollbarPainterForceFlashScrollers(WKScrollbarPainterControllerRef controller)
 {
     [controller flashScrollers];
 }
 
 bool isScrollbarOverlayAPIAvailable()
 {
-    // TODO(sail): Disable overlay scrollbars for now until the following issues are fixed:
-    // #1: Invalidation issues causes the scrollbar to leave trailing artifacts.
-    // #2: Various messages such as live resize started/ended need to be piped from the UI.
-    // #3: Find tick marks need to be drawn on the scrollbar track.
-    // #4: Need to have the theme engine draw the thumb.
-    return false;
-
     static bool apiAvailable = [lookUpNSScrollerImpClass() respondsToSelector:@selector(scrollerImpWithStyle:controlSize:horizontal:replacingScrollerImp:)] &&
                                [lookUpNSScrollerImpPairClass() instancesRespondToSelector:@selector(scrollerStyle)];
     return apiAvailable;
 }
 
 #endif // USE(WK_SCROLLBAR_PAINTER)