Inner class TextWriter in StyledText can be static

Done with JDT clean-up.

Change-Id: I469a39f5d0c289922a8b5260d95343d97df28187
Signed-off-by: Lars Vogel <Lars.Vogel@vogella.com>
Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.swt/+/186595
Tested-by: Platform Bot <platform-bot@eclipse.org>

Author: vogella

bundles/org.eclipse.swt/Eclipse SWT Custom Widgets/common/org/eclipse/swt/custom/StyledText.java

@@ -1046,7 +1046,7 @@ void writeStyledLine(String line, int lineOffset, int ranges[], StyleRange[] sty
 	 * has been called.
 	 * </p>
 	 */
-	class TextWriter {
+	static class TextWriter {
 		private StringBuilder buffer;
 		private int startOffset;	// offset of first character that will be written
 		private int endOffset;		// offset of last character that will be written.