Fix UMR (valgrind) bug in GrDrawingManager

Even prior to https://skia-review.googlesource.com/c/skia/+/332600
(Change UnrefDDLTask to just be the DDLTask) there was no good reason
the 'fRenderTask' array and the 'idArray' kept a strict 1-1
correspondence.

Change-Id: Ib92b47b724c319f52fff459d3dc28c49c17bd045
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/333576
Reviewed-by: Julia Lavrova <jlavrova@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
1 file changed