[Mac] Rework raw keyDown/textInput handling (#12774)

Author: Gillibald

native/Avalonia.Native/src/OSX/AvnView.mm

@@ -537,11 +537,13 @@ - (void)flagsChanged:(NSEvent *)event
 - (void)keyDown:(NSEvent *)event
 {
     _lastKeyHandled = false;
-        
+    
     [self keyboardEvent:event withType:KeyDown];
+        
+    BOOL isKeyDownConsumed = [[self inputContext] handleEvent:event];
 
     if(!_lastKeyHandled){
-        [[self inputContext] handleEvent:event];
+        _lastKeyHandled = isKeyDownConsumed == YES;
     }
 }
 
@@ -552,7 +554,6 @@ - (void)keyUp:(NSEvent *)event
 }
 
 - (void) doCommandBySelector:(SEL)selector{
-    
 }
 
 - (AvnInputModifiers)getModifiers:(NSEventModifierFlags)mod
@@ -599,8 +600,6 @@ - (NSRange)selectedRange
 
 - (void)setMarkedText:(id)string selectedRange:(NSRange)selectedRange replacementRange:(NSRange)replacementRange
 {
-    _lastKeyHandled = true;
-    
     NSString* markedText;
 
     if([string isKindOfClass:[NSAttributedString class]])
@@ -669,8 +668,7 @@ - (void)insertText:(id)string replacementRange:(NSRange)replacementRange
 
     uint64_t timestamp = static_cast<uint64_t>([NSDate timeIntervalSinceReferenceDate] * 1000);
 
-    _lastKeyHandled = _parent->BaseEvents->RawTextInputEvent(timestamp, [text UTF8String]);
-    
+    _parent->BaseEvents->RawTextInputEvent(timestamp, [text UTF8String]);
 }
 
 - (NSUInteger)characterIndexForPoint:(NSPoint)point