screen_ui: Fix an issue when displaying wrapped text.

The last character at EOL is cut when showing the prompt-for-data-wipe
message on angler. Address the issue by keeping symmetrical margins
based on the given offset.

Test: Trigger prompt-and-wipe-data menu. No cutout character at EOL.
Change-Id: Id6e8dc7815bf681435bcaf13e7bdd09cf870d95f
diff --git a/screen_ui.h b/screen_ui.h
index d4923f5..293696d 100644
--- a/screen_ui.h
+++ b/screen_ui.h
@@ -224,8 +224,9 @@
   virtual void DrawTextIcon(int x, int y, GRSurface* surface) const;
   // Draws multiple text lines. Returns the offset it should be moving along Y-axis.
   int DrawTextLines(int x, int y, const std::vector<std::string>& lines) const;
-  // Similar to DrawTextLines() to draw multiple text lines, but additionally wraps long lines.
-  // Returns the offset it should be moving along Y-axis.
+  // Similar to DrawTextLines() to draw multiple text lines, but additionally wraps long lines. It
+  // keeps symmetrical margins of 'x' at each end of a line. Returns the offset it should be moving
+  // along Y-axis.
   int DrawWrappedTextLines(int x, int y, const std::vector<std::string>& lines) const;
 
   Icon currentIcon;