macosx: correctly hide the fspanel if app resigns active state (close #12277)

awakeFromNib is no longer called on fspanel (as there is no nib anymore), so don't rely on it

(cherry picked from commit 51d5f1efb0e77d254d3754c6cf5f6a9856365c52)

modules/gui/macosx/fspanel.h

@@ -45,7 +45,6 @@
                 styleMask: (NSUInteger)aStyle
                   backing: (NSBackingStoreType)bufferingType
                     defer: (BOOL)flag;
-- (void)awakeFromNib;
 - (BOOL)canBecomeKeyWindow;
 - (void)dealloc;
 

modules/gui/macosx/fspanel.m

@@ -48,6 +48,10 @@
                     defer:(BOOL)flag
 {
     id win = [super initWithContentRect:contentRect styleMask:NSTexturedBackgroundWindowMask backing:bufferingType defer:flag];
+
+    if (!win)
+        return win;
+
     self.contentView = [[VLCFSPanelView alloc] initWithFrame:contentRect];
     [win setOpaque:NO];
     [win setHasShadow: NO];
@@ -61,11 +65,7 @@
     hideAgainTimer = fadeTimer = nil;
     [self setFrameAutosaveName:@"fspanel"];
     [self setNonActive:nil];
-    return win;
-}
 
-- (void)awakeFromNib
-{
     [self setContentView:[[VLCFSPanelView alloc] initWithFrame: [self frame]]];
     BOOL isInside = (NSPointInRect([NSEvent mouseLocation],[self frame]));
     [[self contentView] addTrackingRect:[[self contentView] bounds] owner:self userData:nil assumeInside:isInside];
@@ -91,6 +91,8 @@
      selector: @selector(setActive:)
      name: NSApplicationDidBecomeActiveNotification
      object: NSApp];
+
+    return win;
 }
 
 /* make sure that we don't become key, since we can't handle hotkeys */