Update marked text before selection so textInRange is never called with (flutter#6989)

invalid input

Author: justinmc

shell/platform/darwin/ios/framework/Source/FlutterTextInputPlugin.mm

@@ -216,6 +216,14 @@ - (void)setTextInputState:(NSDictionary*)state {
     [self.text setString:newText];
   }
 
+  NSInteger composingBase = [state[@"composingBase"] intValue];
+  NSInteger composingExtent = [state[@"composingExtent"] intValue];
+  NSRange composingRange = [self clampSelection:NSMakeRange(MIN(composingBase, composingExtent),
+                                                            ABS(composingBase - composingExtent))
+                                        forText:self.text];
+  self.markedTextRange =
+      composingRange.length > 0 ? [FlutterTextRange rangeWithNSRange:composingRange] : nil;
+
   NSInteger selectionBase = [state[@"selectionBase"] intValue];
   NSInteger selectionExtent = [state[@"selectionExtent"] intValue];
   NSRange selectedRange = [self clampSelection:NSMakeRange(MIN(selectionBase, selectionExtent),
@@ -233,14 +241,6 @@ - (void)setTextInputState:(NSDictionary*)state {
     [self.inputDelegate selectionDidChange:self];
   }
 
-  NSInteger composingBase = [state[@"composingBase"] intValue];
-  NSInteger composingExtent = [state[@"composingExtent"] intValue];
-  NSRange composingRange = [self clampSelection:NSMakeRange(MIN(composingBase, composingExtent),
-                                                            ABS(composingBase - composingExtent))
-                                        forText:self.text];
-  self.markedTextRange =
-      composingRange.length > 0 ? [FlutterTextRange rangeWithNSRange:composingRange] : nil;
-
   if (textChanged) {
     [self.inputDelegate textDidChange:self];