Update previews after doing a find/replace (#7242)

This commit addresses #7242 for normal Find/Replace. That issue was
fixed for Advanced Find at 29948eec.

(cherry picked from commit 66f527e417)

Added status.

src/lyxfind.cpp

@@ -386,6 +386,7 @@ bool lyxreplace(BufferView * bv,
 		else
 			bv->message(_("String not found."));
 	}
+	bv->buffer().updatePreviews();
 	return update;
 }
 

status.21x

@@ -179,6 +179,8 @@ What's new
 - Remove conflicting accelerator to "Master's perspective" in the
   View Source pane (bug 9495).
 
+- Update previews after find/replace (bug 7242).
+
 
 * INTERNALS