Bug 1880373 - avoid failing browser_test_procinfo.js when a process' …

…CPU time is only 1ms less than the total of its threads' CPU time, r=gerard-majax.

Depends on D201890

Differential Revision: https://phabricator.services.mozilla.com/D201891

UltraBlame original commit: dbe553dd13b79a3c4821f203f3adca31fe71cc56

toolkit/components/processtools/tests/browser/browser_test_procinfo.js

@@ -201,19 +201,65 @@ NS_PER_MS
 )
 ;
 }
+/
+/
+Add
+1ms
+to
+the
+process
+CPU
+time
+because
+ProcInfo
+captures
+the
+CPU
+time
+for
+/
+/
+the
+whole
+process
+first
+and
+then
+for
+each
+of
+the
+threads
+so
+the
+process
+/
+/
+CPU
+time
+might
+have
+increased
+slightly
+in
+the
+meantime
+.
 let
 processCpuTime
 =
 Math
 .
-ceil
+floor
 (
 proc
 .
 cpuTime
 /
 NS_PER_MS
 )
++
+1
 ;
 if
 (