Alternate NTP Mac: Push down overlay in presentation mode

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_separator_view.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_view.h"
 
 @interface OverlayableContentsController()
 - (void)viewDidResize:(NSNotification*)note;
 - (void)layoutViews;
 - (CGFloat)overlayHeightInPixels;
 - (BOOL)shouldShowTopSeparator;
 @end
 
 @implementation OverlayableContentsController
 
 @synthesize drawDropShadow = drawDropShadow_;
 @synthesize activeContainerOffset = activeContainerOffset_;
+@synthesize overlayContentsOffset = overlayContentsOffset_;
 
 - (id)initWithBrowser:(Browser*)browser
      windowController:(BrowserWindowController*)windowController {
   if ((self = [super init])) {
     windowController_ = windowController;
     scoped_nsobject<NSView> view([[NSView alloc] initWithFrame:NSZeroRect]);
     [view setAutoresizingMask:NSViewHeightSizable | NSViewWidthSizable];
     [view setAutoresizesSubviews:NO];
     [[NSNotificationCenter defaultCenter]
         addObserver:self
@@ skipping 103 matching lines @@
 }
 
 - (void)setActiveContainerOffset:(CGFloat)activeContainerOffset {
   if (activeContainerOffset_ == activeContainerOffset)
     return;
 
   activeContainerOffset_ = activeContainerOffset;
   [self layoutViews];
 }
 
+- (void)setOverlayContentsOffset:(CGFloat)overlayContentsOffset {
+  if (overlayContentsOffset_ == overlayContentsOffset)
+    return;
+
+  overlayContentsOffset_ = overlayContentsOffset;
+  [self layoutViews];
+}
+
 - (void)viewDidResize:(NSNotification*)note {
   [self layoutViews];
 }
 
 - (void)layoutViews {
   NSRect bounds = [[self view] bounds];
 
   // Layout the separator at the top of the view.
   NSRect separatorRect = bounds;
   if ([self shouldShowTopSeparator])
     separatorRect.size.height = [OverlayTopSeparatorView preferredHeight];
   else
     separatorRect.size.height = 0;
   separatorRect.origin.y = NSMaxY(bounds) - NSHeight(separatorRect);
   [topSeparatorView_ setFrame:separatorRect];
 
   // Layout the overlay.
   if (overlayContents_) {
     NSRect overlayFrame = bounds;
     overlayFrame.size.height = [self overlayHeightInPixels];
-    overlayFrame.origin.y =
-        NSMinY([topSeparatorView_ frame]) - NSHeight(overlayFrame);
+    overlayFrame.origin.y = NSMinY([topSeparatorView_ frame]) -
+                            NSHeight(overlayFrame) - overlayContentsOffset_;
     [overlayContents_->GetView()->GetNativeView() setFrame:overlayFrame];
 
     if (dropShadowView_) {
       NSRect dropShadowFrame = bounds;
       dropShadowFrame.size.height =
           [OverlayBottomSeparatorView preferredHeight];
       dropShadowFrame.origin.y =
           NSMinY(overlayFrame) - NSHeight(dropShadowFrame);
       [dropShadowView_ setFrame:dropShadowFrame];
     }
   }
 
   // Layout the active tab contents.
   NSRect activeFrame = bounds;
   if (activeContainerOffset_)
     activeFrame.size.height -= activeContainerOffset_;
   else
     activeFrame.size.height -= NSHeight([topSeparatorView_ frame]);
   if (!NSEqualRects(activeFrame, [activeContainer_ frame])) {
     [[activeContainer_ window] disableScreenUpdatesUntilFlush];
     [activeContainer_ setFrame:activeFrame];
   }
 }
 
 - (CGFloat)overlayHeightInPixels {
-  CGFloat height =
-      NSHeight([[self view] bounds]) - NSHeight([topSeparatorView_ frame]);
+  CGFloat height = NSHeight([[self view] bounds]) -
+                   NSHeight([topSeparatorView_ frame]) - overlayContentsOffset_;
   switch (overlayHeightUnits_) {
     case INSTANT_SIZE_PERCENT:
       return std::min(height, (height * overlayHeight_) / 100);
     case INSTANT_SIZE_PIXELS:
       return std::min(height, overlayHeight_);
   }
 }
 
 - (BOOL)shouldShowTopSeparator {
   // In presentation mode tab contents are flush with the top of the screen
   // so there's no need for a separator.
   if ([windowController_ inPresentationMode])
     return NO;
 
   if (![windowController_ hasToolbar])
     return NO;
 
   // Show a separator is the overlay or the tab contents will be shown right
   // next to the omnibox.
   return activeContainerOffset_ == 0 || overlayContents_;
 }
 
 @end