Revert "Defer mip-mapping until lazy proxy instantiation"

This reverts commit 475819cab73082c7ff33c3bf5c56b3871cdc1280.

Reason for revert: No, let's not defer.

Original change's description:
> Defer mip-mapping until lazy proxy instantiation
> 
> - Remove some checks for truly impossible failures (levelCount < 0)
> - Use helper method to predict number of mips, then verify correct
>   results in the lambda.
> - Split up SkMipMap::Build with a CanBuild helper, so GPU code can
>   predict success/failure accurately.
> - This is going to simplify the case where we need to change the
>   config for unsupported formats.
> 
> Bug: skia:8375
> Change-Id: Ied523ab55c38b8c8e7e2ae983744ed400497939b
> Reviewed-on: https://skia-review.googlesource.com/154080
> Commit-Queue: Brian Osman <brianosman@google.com>
> Reviewed-by: Robert Phillips <robertphillips@google.com>

TBR=bsalomon@google.com,robertphillips@google.com,brianosman@google.com,reed@google.com

Change-Id: I04dbc458103f7bb5a7c28da28b0256d7a2b8b3d3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:8375
Reviewed-on: https://skia-review.googlesource.com/154304
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
3 files changed