Fix only-callable once setPriority/sendReportTo language (#745)

* Fix only-callable once setPriority/sendReportTo language

The way it was spec'd it was actually callable an odd number of times,
since the state on failure got reset to null, and it failed to throw an
exception for that in setPriority. Instead, shift the state to failure
and stay there on extra calls.

* Apply feedback

---------

Co-authored-by: Maks Orlovich <morlovich@chromium.org>

spec.bs

@@ -2159,7 +2159,7 @@ of the following global objects:
       « |igJS|, |auctionSignalsJS|, |perBuyerSignalsJS|, |trustedBiddingSignalsJS|, |browserSignalsJS| »,
       and |timeout|.
     1. Let |duration| be the [=current wall time=] minus |startTime| in milliseconds.
-    1. If |global|'s [=InterestGroupBiddingScriptRunnerGlobalScope/priority=] is not null:
+    1. If |global|'s [=InterestGroupBiddingScriptRunnerGlobalScope/priority=] is not null and not failure:
       1. Set |ig|'s [=interest group/priority=] to |global|'s
         [=InterestGroupBiddingScriptRunnerGlobalScope/priority=].
       1. [=list/Replace=] the [=interest group=] that has |ig|'s [=interest group/owner=] and
@@ -2222,7 +2222,9 @@ of the following global objects:
 
       Note: Consider a return value that can't be converted to JSON a valid result, so if an
       exception was [=exception/thrown=] in the previous step, keep |resultJSON| as "null".
-    1. Return « |resultJSON|, |global|'s [=InterestGroupReportingScriptRunnerGlobalScope/report url=],
+    1. Let |reportURL| be |global|'s [=InterestGroupReportingScriptRunnerGlobalScope/report url=]
+    1. If |reportURL| is failure, set |reportURL| to null.
+    1. Return « |resultJSON|, |reportURL|,
        |global|'s [=InterestGroupReportingScriptRunnerGlobalScope/reporting beacon map=] ».
 </div>
 
@@ -2328,7 +2330,7 @@ Each {{InterestGroupBiddingScriptRunnerGlobalScope}} has a
 : <dfn>bid</dfn>
 :: A [=generated bid=]
 : <dfn>priority</dfn>
-:: Null or a {{double}}
+:: Null, failure, or a {{double}}. Defaulting to null.
 : <dfn>priority signals</dfn>
 :: An [=ordered map=] whose [=map/keys=] are [=strings=] and whose [=map/values=] are {{double}} or null.
 : <dfn>interest group</dfn>
@@ -2497,8 +2499,8 @@ To <dfn>convert GenerateBidOutput to generated bid</dfn> given a {{GenerateBidOu
   1. If [=this=]'s [=relevant global object=]'s
     [=InterestGroupBiddingScriptRunnerGlobalScope/priority=] is not null:
     1. Set [=this=]'s [=relevant global object=]'s
-      [=InterestGroupBiddingScriptRunnerGlobalScope/priority=] to null.
-    1. Return.
+      [=InterestGroupBiddingScriptRunnerGlobalScope/priority=] to failure.
+    1. [=exception/Throw=] a {{TypeError}}.
   1. Set [=this=]'s [=relevant global object=]'s
     [=InterestGroupBiddingScriptRunnerGlobalScope/priority=] to |priority|.
 </div>
@@ -2540,7 +2542,7 @@ interface InterestGroupReportingScriptRunnerGlobalScope
 Each {{InterestGroupReportingScriptRunnerGlobalScope}} has a
 <dl dfn-for="InterestGroupReportingScriptRunnerGlobalScope">
 : <dfn>report url</dfn>
-:: Null or a [=URL=]. Defaulting to null.
+:: Null, failure, or a [=URL=]. Defaulting to null.
 : <dfn>reporting beacon map</dfn>
 :: Null or an [=ordered map=] whose [=map/keys=] are [=strings=] and whose [=map/values=] are
   [=URLs=]. Defaulting to null.
@@ -2554,11 +2556,13 @@ Each {{InterestGroupReportingScriptRunnerGlobalScope}} has a
   1. If [=this=]'s [=relevant global object=]'s
     [=InterestGroupReportingScriptRunnerGlobalScope/report url=] is not null:
     1. Set [=this=]'s [=relevant global object=]'s
-      [=InterestGroupReportingScriptRunnerGlobalScope/report url=] to null.
+      [=InterestGroupReportingScriptRunnerGlobalScope/report url=] to failure.
     1. [=exception/Throw=] a {{TypeError}}.
   1. Let |parsedUrl| be the result of running the [=URL parser=] on |url|.
   1. If |parsedUrl| is failure, or |parsedUrl|'s [=url/scheme=] is not "`https`",
-    [=exception/Throw=] a {{TypeError}}.
+    set  [=this=]'s [=relevant global object=]'s
+      [=InterestGroupReportingScriptRunnerGlobalScope/report url=] to failure
+      and [=exception/Throw=] a {{TypeError}}.
   1. Set [=this=]'s [=relevant global object=]'s
     [=InterestGroupReportingScriptRunnerGlobalScope/report url=] to |parsedUrl|.
 </div>