Instant: Use only one hidden WebContents per profile.

chrome/browser/ui/cocoa/tab_contents/overlayable_contents_controller.mm

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/ui/cocoa/tab_contents/overlayable_contents_controller.h"
 
 #include "base/mac/bundle_locations.h"
 #include "chrome/browser/ui/cocoa/browser_window_controller.h"
 #include "chrome/browser/ui/cocoa/tab_contents/instant_overlay_controller_mac.h"
 #include "chrome/browser/ui/cocoa/tab_contents/overlay_drop_shadow_view.h"
@@ skipping 40 matching lines @@
 }
 
 - (void)setOverlay:(content::WebContents*)overlay
             height:(CGFloat)height
        heightUnits:(InstantSizeUnits)heightUnits
     drawDropShadow:(BOOL)drawDropShadow {
   // If drawing drop shadow, clip the bottom 1-px-thick separator out of
   // overlay.
   // TODO(sail): remove this when GWS gives chrome the height without the
   // separator.
-  if (drawDropShadow && heightUnits != INSTANT_SIZE_PERCENT)
+  if (drawDropShadow && heightUnits == INSTANT_SIZE_PIXELS)
     --height;
 
   if (overlayContents_ == overlay &&
       overlayHeight_ == height &&
       overlayHeightUnits_ == heightUnits &&
       drawDropShadow_ == drawDropShadow) {
     return;
   }
 
   // Remove any old overlay contents before showing the new one.
@@ skipping 100 matching lines @@
   CGFloat height = NSHeight([[self view] bounds]);
   switch (overlayHeightUnits_) {
     case INSTANT_SIZE_PERCENT:
       return std::min(height, (height * overlayHeight_) / 100);
     case INSTANT_SIZE_PIXELS:
       return std::min(height, overlayHeight_);
   }
 }
 
 @end