CupsProxyService dropping 'job-sheets*' attributes

The job-sheets* IPP attribute is behaving unexpectedly; until
crbug.com/1010629 is resolved, we'll just drop these attributes to not gate
printing via cups_proxy.

Bug: crbug.com/1010629
Test: confirmed printing via lp with the cups_proxy succeeds
Change-Id: I5e5443647a3d7d4d7a1834d524eacd22688851df
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1838491
Commit-Queue: Luum Habtemariam <luum@chromium.org>
Reviewed-by: Sean Kau <skau@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703447}

chrome/services/cups_proxy/ipp_attribute_validator.cc

@@ -75,9 +75,11 @@ ValidateAttributeResult ValidateAttribute(ipp_op_t ipp_oper_id,
       {"job-priority-default", {false, ValueType::INTEGER}},
       {"job-priority-supported", {false, ValueType::INTEGER}},
       {"job-quota-period", {false, ValueType::INTEGER}},
-      {"job-sheets", {false, ValueType::STRING}},
-      {"job-sheets-default", {false, ValueType::STRING}},
-      {"job-sheets-supported", {true, ValueType::STRING}},
+      // TODO(crbug.com/1010629): Removed these attributes so they get dropped
+      // from incoming requests, rather than being validated.
+      // {"job-sheets", {false, ValueType::STRING}},
+      // {"job-sheets-default", {false, ValueType::STRING}},
+      // {"job-sheets-supported", {true, ValueType::STRING}},
       {"job-state", {false, ValueType::INTEGER}},
       {"job-state-reasons", {true, ValueType::STRING}},
       {"job-uri", {false, ValueType::STRING}},