Fixes #2196. TextView: Setting Text places cursor at beginning, unlike TextField (#2572)

* Fixes #2196. TextView: Setting Text places cursor at beginning, unlike TextField

* Change all private members to have the _prefix.

* Renamed local member to prevLayoutStyle.

* Helper function for SetNeedsDisplay.

UnitTests/Views/TextFieldTests.cs

@@ -1588,5 +1588,15 @@ Les Miśerables", output);
 			tf.ProcessKey (new KeyEvent (Key.CtrlMask | Key.CursorRight, new KeyModifiers () { Ctrl = true }));
 			Assert.Equal (22, tf.CursorPosition);
 		}
+
+		[Fact, TextFieldTestsAutoInitShutdown]
+		public void Cursor_Position_Initialization ()
+		{
+			Assert.False (_textField.IsInitialized);
+			Assert.Equal (32, _textField.CursorPosition);
+			Assert.Equal (0, _textField.SelectedLength);
+			Assert.Null (_textField.SelectedText);
+			Assert.Equal ("TAB to jump between text fields.", _textField.Text);
+		}
 	}
 }

UnitTests/Views/TextViewTests.cs

@@ -6934,5 +6934,19 @@ This is the second line.
 			newPos = model.WordForward (4, 0);
 			Assert.Null (newPos);
 		}
+
+		[Fact, TextViewTestsAutoInitShutdown]
+		public void Cursor_Position_Multiline_False_Initialization ()
+		{
+			Assert.False (_textView.IsInitialized);
+			Assert.True (_textView.Multiline);
+			_textView.Multiline = false;
+			Assert.Equal (32, _textView.CursorPosition.X);
+			Assert.Equal (0, _textView.CursorPosition.Y);
+			Assert.Equal (0, _textView.SelectedLength);
+			Assert.Equal ("", _textView.SelectedText);
+			Assert.Equal ("TAB to jump between text fields.", _textView.Text);
+		}
+
 	}
 }