allocate GrAtlasTextOp::Geometry on heap

I was mistaken about the life time of the RecordTimeAllocator.
Just allocate the geometries in the heap until an allocator can
be put on the GrSurfaceDrawContext.

Bug: b/182959903

Change-Id: I2378bf3c225acf3dfc153daf6eebb6cbf8ebbaff
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/391556
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Herb Derby <herb@google.com>
3 files changed