iOS: Avoid category method name clash for UIResponder

As described in Apples documentation, own methods which are added to
existing classes should be prefixed to avoid category method name
clashes. This prefix was missing from the function
currentFirstResponder() which caused issues when closing the virtual
keyboard on some iOS devices.
(see https://developer.apple.com/library/archive/qa/qa1908/_index.html)

Pick-to: 6.6 6.5
Task-number: QTBUG-119601
Change-Id: I82fb8a8beeb0a3234594357f1e1db67b0ae3da36
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
(cherry picked from commit e51b2d70de65f2ac674afb9c7da2a10c7067f142)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

src/plugins/platforms/ios/qiosglobal.h

@@ -37,7 +37,7 @@ int infoPlistValue(NSString* key, int defaultValue);
 QT_END_NAMESPACE
 
 @interface UIResponder (QtFirstResponder)
-+ (id)currentFirstResponder;
++ (id)qt_currentFirstResponder;
 @end
 
 QT_BEGIN_NAMESPACE

src/plugins/platforms/ios/qiosglobal.mm

@@ -119,7 +119,7 @@ QT_END_NAMESPACE
 
 @implementation UIResponder (QtFirstResponder)
 
-+ (id)currentFirstResponder
++ (id)qt_currentFirstResponder
 {
     if (qt_apple_isApplicationExtension()) {
         qWarning() << "can't get first responder in application extensions!";

src/plugins/platforms/ios/qiosinputcontext.mm

@@ -121,7 +121,7 @@ static QUIView *focusView()
 {
     [self keyboardWillOrDidChange:notification];
 
-    UIResponder *firstResponder = [UIResponder currentFirstResponder];
+    UIResponder *firstResponder = [UIResponder qt_currentFirstResponder];
     if (![firstResponder isKindOfClass:[QIOSTextInputResponder class]])
         return;
 
@@ -234,7 +234,7 @@ static QUIView *focusView()
 
     if (self.state == UIGestureRecognizerStateBegan) {
         qImDebug("hide keyboard gesture was triggered");
-        UIResponder *firstResponder = [UIResponder currentFirstResponder];
+        UIResponder *firstResponder = [UIResponder qt_currentFirstResponder];
         Q_ASSERT([firstResponder isKindOfClass:[QIOSTextInputResponder class]]);
         [firstResponder resignFirstResponder];
     }

src/plugins/platforms/ios/qiosmenu.mm

@@ -491,7 +491,7 @@ QIOSMenuItemList QIOSMenu::filterFirstResponderActions(const QIOSMenuItemList &m
     // In case of QIOSTextResponder, edit actions will be converted to key events that ends up
     // triggering the shortcuts of the filtered menu items.
     QIOSMenuItemList filteredMenuItems;
-    UIResponder *responder = [UIResponder currentFirstResponder];
+    UIResponder *responder = [UIResponder qt_currentFirstResponder];
 
     for (int i = 0; i < menuItems.count(); ++i) {
         QIOSMenuItem *menuItem = menuItems.at(i);

src/plugins/platforms/ios/qiostextresponder.mm

@@ -164,7 +164,7 @@
 {
     FirstResponderCandidate firstResponderCandidate(self);
 
-    qImDebug() << "self:" << self << "first:" << [UIResponder currentFirstResponder];
+    qImDebug() << "self:" << self << "first:" << [UIResponder qt_currentFirstResponder];
 
     if (![super becomeFirstResponder]) {
         qImDebug() << self << "was not allowed to become first responder";
@@ -178,7 +178,7 @@
 
 - (BOOL)resignFirstResponder
 {
-    qImDebug() << "self:" << self << "first:" << [UIResponder currentFirstResponder];
+    qImDebug() << "self:" << self << "first:" << [UIResponder qt_currentFirstResponder];
 
     // Don't allow activation events of the window that we're doing text on behalf on
     // to steal responder.
@@ -196,11 +196,11 @@
     // a regular responder transfer to another window. In the former case, iOS
     // will set the new first-responder to our next-responder, and in the latter
     // case we'll have an active responder candidate.
-    if (![UIResponder currentFirstResponder] && !FirstResponderCandidate::currentCandidate()) {
+    if (![UIResponder qt_currentFirstResponder] && !FirstResponderCandidate::currentCandidate()) {
         // No first responder set anymore, sync this with Qt by clearing the
         // focus object.
         m_inputContext->clearCurrentFocusObject();
-    } else if ([UIResponder currentFirstResponder] == [self nextResponder]) {
+    } else if ([UIResponder qt_currentFirstResponder] == [self nextResponder]) {
         // We have resigned the keyboard, and transferred first responder back to the parent view
         Q_ASSERT(!FirstResponderCandidate::currentCandidate());
         if ([self currentImeState:Qt::ImEnabled].toBool()) {

src/plugins/platforms/ios/quiview.mm

@@ -304,7 +304,7 @@ inline ulong getTimeStamp(UIEvent *event)
         // blocked by this guard.
         FirstResponderCandidate firstResponderCandidate(self);
 
-        qImDebug() << "self:" << self << "first:" << [UIResponder currentFirstResponder];
+        qImDebug() << "self:" << self << "first:" << [UIResponder qt_currentFirstResponder];
 
         if (![super becomeFirstResponder]) {
             qImDebug() << self << "was not allowed to become first responder";
@@ -343,7 +343,7 @@ inline ulong getTimeStamp(UIEvent *event)
 
 - (BOOL)resignFirstResponder
 {
-    qImDebug() << "self:" << self << "first:" << [UIResponder currentFirstResponder];
+    qImDebug() << "self:" << self << "first:" << [UIResponder qt_currentFirstResponder];
 
     if (![super resignFirstResponder])
         return NO;
@@ -366,7 +366,7 @@ inline ulong getTimeStamp(UIEvent *event)
     if ([self isFirstResponder])
         return YES;
 
-    UIResponder *firstResponder = [UIResponder currentFirstResponder];
+    UIResponder *firstResponder = [UIResponder qt_currentFirstResponder];
     if ([firstResponder isKindOfClass:[QIOSTextInputResponder class]]
         && [firstResponder nextResponder] == self)
         return YES;