Revert "Improve GrPathRendererChain heuristics"

This reverts commit 60f42494f5d45c38e260ce089cdddfb600f799b2.

Reason for revert: breaking gold

Original change's description:
> Improve GrPathRendererChain heuristics
> 
> Changes GrPathRenderer::canDrawPath to return a 'CanDrawPath' enum,
> which contains a new kAsBackup value that means "I'm better than SW,
> but give the path renderers below me a chance first."
> 
> Bug: skia:
> Change-Id: I45aac5462ca1bc0bc839eb1c315db9493901a07e
> Reviewed-on: https://skia-review.googlesource.com/42222
> Reviewed-by: Brian Osman <brianosman@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Chris Dalton <csmartdalton@google.com>

TBR=jvanverth@google.com,bsalomon@google.com,brianosman@google.com,csmartdalton@google.com,senorblanco@google.com

Change-Id: I46020dbd56b6f6b88668894285b9b7b80f89b9a2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/43780
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
25 files changed