Revert of Mac: Fix rounded corners on browser windows on retina display.

chrome/browser/ui/cocoa/browser_window_controller_private.mm

Index: chrome/browser/ui/cocoa/browser_window_controller_private.mm
diff --git a/chrome/browser/ui/cocoa/browser_window_controller_private.mm b/chrome/browser/ui/cocoa/browser_window_controller_private.mm
index 234af6bd046ef7bb0558444cb50a30726484b95c..b186e280af07333d67c42e96e953af025d4f386e 100644
--- a/chrome/browser/ui/cocoa/browser_window_controller_private.mm
+++ b/chrome/browser/ui/cocoa/browser_window_controller_private.mm
@@ -520,10 +520,6 @@ willPositionSheet:(NSWindow*)sheet
   }
 }
 
-- (void)updateRoundedBottomCorners {
-  [[self tabContentArea] setRoundedBottomCorners:![self isInAnyFullscreenMode]];
-}
-
 - (void)adjustToolbarAndBookmarkBarForCompression:(CGFloat)compression {
   CGFloat newHeight =
       [toolbarController_ desiredHeightForCompression:compression];
@@ -920,7 +916,6 @@ willPositionSheet:(NSWindow*)sheet
   [self showFullscreenExitBubbleIfNecessary];
   browser_->WindowFullscreenStateChanged();
   [[[self window] cr_windowView] setWantsLayer:windowViewWantsLayer_];
-  [self updateRoundedBottomCorners];
 }
 
 - (void)windowWillExitFullScreen:(NSNotification*)notification {
@@ -934,7 +929,6 @@ willPositionSheet:(NSWindow*)sheet
   if (notification)  // For System Fullscreen when non-nil.
     [self deregisterForContentViewResizeNotifications];
   browser_->WindowFullscreenStateChanged();
-  [self updateRoundedBottomCorners];
 }
 
 - (void)windowDidFailToEnterFullScreen:(NSWindow*)window {