[Mac] Retain location bar focus on switching to fullscreen and back.

chrome/browser/ui/cocoa/browser_window_controller_private.mm

 // Copyright (c) 2012 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/browser_window_controller_private.h"
 
 #include <cmath>
 
 #import "base/auto_reset.h"
 #include "base/command_line.h"
@@ skipping 944 matching lines @@
     [subviews addObject:[bookmarkBarController_ view]];
   if ([toolbarController_ view])
     [subviews addObject:[toolbarController_ view]];
   if ([infoBarContainerController_ view])
     [subviews addObject:[infoBarContainerController_ view]];
   if ([self tabContentArea])
     [subviews addObject:[self tabContentArea]];
   if ([findBarCocoaController_ view])
     [subviews addObject:[findBarCocoaController_ view]];
 
+  // -setContentViewSubviews: changes the view hierarchy. As a result, if the
+  // location bar is focused it will end up resigning first responder.
+  // Remember the location bar's focus state and restore it after changing the
+  // view hierarchy.
+  BOOL locationBarHadFocus = [self locationBarHasFocus];
   [self setContentViewSubviews:subviews];
+  if (locationBarHadFocus)

[spqchan, 2017/02/09 01:50:34]

optional nit:  if ([self locationBarHasFocus]) and get rid of
|locationBarHasFocus|

[shrike, 2017/02/09 02:18:29]

The problem is that [self setContentViewSubviews:subviews] changes the view
hierarchy and forces the location bar to resign first responder. If  [self
locationBarHasFocus] was true before the call to -setContentViewSubviews:, it
will be false afterwards.

[spqchan, 2017/02/09 05:09:36]

Ah, gotcha

+    [self focusLocationBar:YES];
 }
 
 - (void)updateSubviewZOrderFullscreen {
   base::scoped_nsobject<NSMutableArray> subviews([[NSMutableArray alloc] init]);
 
   // The infobar should overlay the toolbar if the toolbar is fully shown.
   FullscreenToolbarLayout layout = [fullscreenToolbarController_ computeLayout];
   BOOL shouldInfoBarOverlayToolbar =
       ui::IsCGFloatEqual(layout.toolbarFraction, 1.0);
 
@@ skipping 19 matching lines @@
 
   if ([toolbarController_ view])
     [subviews addObject:[toolbarController_ view]];
 
   if (shouldInfoBarOverlayToolbar && [infoBarContainerController_ view])
     [subviews addObject:[infoBarContainerController_ view]];
 
   if ([findBarCocoaController_ view])
     [subviews addObject:[findBarCocoaController_ view]];
 
+  // -setContentViewSubviews: changes the view hierarchy, and if the
+  // location bar is focused will cause it to resign first responder.
+  // Remember the location bar's focus state and restore it after changing the
+  // view hierarchy.
+  BOOL locationBarHadFocus = [self locationBarHasFocus];
   [self setContentViewSubviews:subviews];
+  if (locationBarHadFocus) {

[spqchan, 2017/02/09 01:50:34]

Ditto from above

+    [self focusLocationBar:YES];
+  }
 }
 
 - (void)setContentViewSubviews:(NSArray*)subviews {
   // Subviews already match.
   if ([[self.chromeContentView subviews] isEqual:subviews])
     return;
 
   // The tabContentArea isn't a subview, so just set all the subviews.
   NSView* tabContentArea = [self tabContentArea];
   if (![[self.chromeContentView subviews] containsObject:tabContentArea]) {
@@ skipping 176 matching lines @@
   if (fullscreenLowPowerCoordinator_)
     fullscreenLowPowerCoordinator_->SetHasActiveSheet(false);
 }
 
 - (void)childWindowsDidChange {
   if (fullscreenLowPowerCoordinator_)
     fullscreenLowPowerCoordinator_->ChildWindowsChanged();
 }
 
 @end  // @implementation BrowserWindowController(Private)