Update comments in SUPPRESSIONS for xfa_specific

This adds comments for the specific bug associated with each
suppression, and a comment to remove the suppression line once the bug
is fixed.

BUG=pdfium:1020

Change-Id: I8002fe1711c55e39b2ef79c395980c89f6440853
Reviewed-on: https://pdfium-review.googlesource.com/34510
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
diff --git a/testing/SUPPRESSIONS b/testing/SUPPRESSIONS
index c4febdd..417d301 100644
--- a/testing/SUPPRESSIONS
+++ b/testing/SUPPRESSIONS
@@ -318,7 +318,7 @@
 
 # xfa_specific
 
-TODO(dsinclair): Remove after pdfium:1106 is fixed
+# TODO(pdfium:1106): Remove after associated bug is fixed
 resolve_nodes_1.pdf * * *
 
 #
@@ -328,9 +328,10 @@
 
 # xfa_specific
 
-# TODO(rharrison): Create expectations for existing files.
+# TODO(pdfium:1105): Remove after associated bug is fixed
 dynamic_list_box_allow_multiple_selection.pdf * * *
+# TODO(pdfium:1107): Remove after associated bug is fixed
 standard_symbols.pdf * * *
-# TODO(rharrison): Remove these after pdfium:1095 is fixed
+# TODO(pdfium:1095): Remove after associated bug is fixed
 xfa_example.in win * *
 xfa_textfield.in win * *