Calling Paper TextInput setTextAndSelection view command now dirties layout

Summary:
Changelog: [Internal]

Previously `setTextAndSelection` was not dirtying layout. This would cause an issue where `setTextAndSelection` causes layout change. For example calling setTextAndSelection with empty string on a multiline auto expanding text input.

I changed one example in TextInputSharedExamples.js, "Live Re-Write (no spaces allowed) and clear" example is now multiline. This allows to test whether `setTextAndSelection` dirties layout. Enter multiline string to to the example text input and press clear. Observe that the text input shrinks to single line height.

Reviewed By: shergin

Differential Revision: D21182990

fbshipit-source-id: de8501ea0b97012cf4cdf8d5f658649139f92da6

Libraries/Text/TextInput/RCTBaseTextInputView.m

@@ -24,7 +24,6 @@
   __weak RCTEventDispatcher *_eventDispatcher;
   BOOL _hasInputAccesoryView;
   NSString *_Nullable _predictedText;
-  NSInteger _nativeEventCount;
   BOOL _didMoveToWindow;
 }
 
@@ -199,17 +198,9 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithFrame:(CGRect)frame)
   }
 }
 
-- (void)setText:(NSString *__nullable)text
- selectionStart:(NSInteger)start
-   selectionEnd:(NSInteger)end
+- (void)setSelectionStart:(NSInteger)start
+             selectionEnd:(NSInteger)end
 {
-  if (text) {
-    NSMutableAttributedString *mutableString =
-    [[NSMutableAttributedString alloc] initWithAttributedString:self.backedTextInputView.attributedText];
-    [mutableString replaceCharactersInRange:NSMakeRange(0, mutableString.string.length) withString:text];
-    self.backedTextInputView.attributedText = mutableString;
-  }
-
   UITextPosition *startPosition = [self.backedTextInputView positionFromPosition:self.backedTextInputView.beginningOfDocument
                                                                           offset:start];
   UITextPosition *endPosition = [self.backedTextInputView positionFromPosition:self.backedTextInputView.beginningOfDocument