Catch edge case: TextRenderer with POSITION & TOP

Resolve exception in `TextRenderer::updateFontAndText()` when the FONT
property is a String

DEVSIX-1359

Author: Benoit Lagae

layout/src/main/java/com/itextpdf/layout/renderer/TextRenderer.java

@@ -1259,7 +1259,7 @@ private boolean isGlyphPartOfWordForHyphenation(Glyph g) {
 
     private void updateFontAndText() {
         if (strToBeConverted != null) {
-            font = getPropertyAsFont(Property.FONT);
+            font = resolveFirstPdfFont();
             text = convertToGlyphLine(strToBeConverted);
             otfFeaturesApplied = false;
             strToBeConverted = null;

layout/src/test/java/com/itextpdf/layout/renderer/TextRendererTest.java

@@ -48,11 +48,14 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.pdf.PdfWriter;
 import com.itextpdf.layout.Document;
 import com.itextpdf.layout.element.Text;
+import com.itextpdf.layout.font.FontProvider;
 import com.itextpdf.layout.layout.LayoutArea;
 import com.itextpdf.layout.layout.LayoutContext;
 import com.itextpdf.layout.layout.LayoutResult;
+import com.itextpdf.layout.property.Property;
 import com.itextpdf.test.ExtendedITextTest;
 import com.itextpdf.test.annotations.type.UnitTest;
+
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
@@ -84,4 +87,16 @@ public void nextRendererTest() {
         Assert.assertEquals(result1.getOccupiedArea(), result2.getOccupiedArea());
     }
 
+    @Test
+    public void setTextException() {
+        final String val = "other text";
+        final String fontName = "Helvetica";
+        TextRenderer rend = (TextRenderer) new Text("basic text").getRenderer();
+        FontProvider fp = new FontProvider();
+        fp.addFont(fontName);
+        rend.setProperty(Property.FONT_PROVIDER, fp);
+        rend.setProperty(Property.FONT, fontName);
+        rend.setText(val);
+        Assert.assertEquals(val, rend.getText().toString());
+    }
 }