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

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 f084fb039ddfc634afb1cc0415d6dd245e856c66..5cb48760ddcfe063f7cf2857b6f82784e82695d8 100644
--- a/chrome/browser/ui/cocoa/browser_window_controller_private.mm
+++ b/chrome/browser/ui/cocoa/browser_window_controller_private.mm
@@ -962,7 +962,14 @@ willPositionSheet:(NSWindow*)sheet
   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 {
@@ -1002,7 +1009,15 @@ willPositionSheet:(NSWindow*)sheet
   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 {